50byn

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Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

PC 111 Catalog No. 535-00136 Printed in U.S.A. Form 50BYN-1SI Pg 1 2-04 Replaces: 50BY-1SBook 1 4

Ta b 2 b 7a

Installation, Start-Up and

Service InstructionsCONTENTS

Page

SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . 1

GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13Step 1 Complete Pre-Installation Checks . . . . . . 1Step 2 Rig and Place Unit . . . . . . . . . . . . . . . . . . . . . 2Splitting a 50BYN024 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Unit Discharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Vibration Isolation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Step 3 Install Accessories . . . . . . . . . . . . . . . . . . . . . 2

Step 4 Install Ductwork. . . . . . . . . . . . . . . . . . . . . . . . 7Step 5 Install Rain/Condensate Drain Line . . . . 11Step 6 Complete Electrical Connections . . . . . . 13START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-20General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Compressor Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Operating Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20, 21Cleaning Evaporator and Condenser Coils . . . . . . 20Lubrication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Condenser Fan Adjustment . . . . . . . . . . . . . . . . . . . . . 20Pulley Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Belt Tension Adjustment . . . . . . . . . . . . . . . . . . . . . . . . 20Changing Fan Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Fan Bearing Replacement . . . . . . . . . . . . . . . . . . . . . . . 20

Concentric Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . 20MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21, 22Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Air Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Condensate Drain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Checking System Charge . . . . . . . . . . . . . . . . . . . . . . . 21Access Panel Removal . . . . . . . . . . . . . . . . . . . . . . . . . . 22Evaporator-Fan Motor Removal . . . . . . . . . . . . . . . . . 22Pressure Relief Device . . . . . . . . . . . . . . . . . . . . . . . . . . 22Cycle-LOC Protection Device . . . . . . . . . . . . . . . . . 22Time Guard II Control . . . . . . . . . . . . . . . . . . . . . . . . . . . 22High and Low Pressurestats . . . . . . . . . . . . . . . . . . . . 22Oil Charge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

TROUBLESHOOTING. . . . . . . . . . . . . . . . . . . . . . . . . 23-25

START-UP CHECKLIST . . . . . . . . . . . . . . . . . . CL-1, CL-2

SAFETY CONSIDERATIONS

Installing, starting up, and servicing air-conditioning com-ponents and equipment can be dangerous. Only trained, quali-fied installers and service mechanics should install, start-up,and service this equipment.

When working on the equipment, observe precautions in theliterature and on tags, stickers, and labels attached to the equip-ment. Follow all safety codes. Wear safety glasses and workgloves.

GENERALOMNIZONE indoor package units are designed to provide

the flexibility required in replacement, renovation, and newconstruction. Units are available in 6 sizes from 5 tons to20 tons. Belt-drive condensers provide adequate static to overcome ducting and louver static losses. This allows units to bepositioned against an existing window or wall louver, or ductedto the outside as required.

Convenient rear connections allow easy access for outsideair connections and air side economizer. Unit supply aidischarge may be vertical or horizontal front. These packagedvertical packaged units are fully piped and wired. Units arecomplete with a belt drive evaporator section and built-inducted air-cooled condenser. Airflow is horizontal or vertical.

All units are designed to fit through most standard doorsThe 20 ton size may be easily field split to simplify moving theunits into existing buildings. See Fig. 1-3 for unit dimensionsand refer to Table 1 for unit operating weights.

INSTALLATION

OMNIZONE 50BY units are intended for indoor installa-tion only. Determine building alterations required to run pipingwiring and ductwork. Follow dimensional drawings for ductwork, piping locations, electrical wiring (refer to Table 2 forelectrical data) and overall unit dimensions.

Read all installation instructions before installing the unit.

Step 1 Complete Pre-Installation

Checks Examine unit for damage incurred during shipment. File claim immediately with transit company if damageis found. Check the shipment for completeness. Verify that thenameplate electrical requirements match the available powersupply.

DO NOT place the unit in a horizontal position that wouldallow oil to drain into the top of the compressor. Do not allowrefrigerant lines to come into contact with wiring or sharp ob-jects or edges. Do not lift or move unit by putting pressure onrefrigerant lines.

Before performing service or maintenance operations onunit, turn off main power switch to unit. Electrical shockcould cause personal injury.

Use care in handling, rigging, and setting bulky equipment.

OMNIZONE50BYN006-024

Air-CooledIndoor Self-Contained Systems

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Step 2 Rig and Place Unit Units are mountedon skids. Leave the unit on the skid until it is in the final posi-tion. While on the skid, the unit can be rolled, dragged or fork-lifted; do not apply force to the unit. Use a minimum of 3 roll-ers when rolling, and raise from above to remove the skid whenunit is in the final position. See Fig. 4 for rigging details.

PLACING THE UNIT The selected unit location shouldnot be adjacent to an acoustically sensitive space. The best lo-cations for these units are mechanical rooms, near elevatorshafts, near restrooms, near stairwells or other similar loca-tions. Position the unit where large supply of outdoor air is

available for the unit inlet. Be sure to leave enough space forthe return air inlet access to the evaporator and condenser coilsfor cleaning and maintenance. Units located on the same floorshould have a minimum of 6 ft of clearance between condenserair openings. Units located floor-to-floor should have a mini-mum of 10 ft between units to prevent recirculation of condi-tioned air. DO NOT locate units where they will recirculateconditioned air. This will cause increased head pressure whichcan cause units to trip on high pressure. See Fig. 1-3 for recom-mended unit clearances and locations.

Either provide inlet filters to protect the coils, or locate theunit in an area free from airborne dirt or other foreign materialwhich could clog the coils.

The units are designed to pass through most 36-in. dooropenings. The filter rack and duct mounting flanges may alsobe removed for additional clearance.

Splitting a 50BYN024 The size 024 unit heightexceeds 80 in. and may not clear all door openings. It may benecessary to split the unit in order to move it into the desiredinstallation location. Refer to the following instructions to splitthe unit:

NOTE: This unit and its 2 sections are heavy. Three peopleare required to move the sections safely. You will also needsafety goggles, gloves and a dolly.

1. Move the unit to a work area close to the final installationlocation.

2. Be certain the service valves for all 3 circuits are in theOFF position. See Fig. 5. If any valves have been

opened, the system must be evacuated.3. Undo the suction line at the threaded fitting between the

upper and lower sections of the unit. See Fig. 6.

4. Mark and undo each of the liquid lines for all 3 circuits atthe threaded connections to the expansion valve and theconnection to the filter drier. See Fig. 6.

5. Carefully move the liquid lines to the side, keeping theminside the unit.

6. You can now separate the upper and lower sections ofthe unit. Remove the 8 bolts that hold the two sectionstogether. See Fig. 7. Once the bolts are removed, save thenuts, bolts and washers for use in re-assembly.

7. Carefully lift the fan/coil section from the base sectionand separate.

8. Move the separate sections to the installation location.9. Place the bottom section first and then place the top sec-

tion on top of it.

10. Bolt the sections together.

11. Reconnect the suction lines with the threaded fittings.

12. Reconnect the liquid lines to the expansion valve andfilter drier. DO NOT mix circuits; be certain each line isreturned to its original location.

13. Connect a vacuum pump to the service port by the com-pressor, on the suction line.

14. Pull a vacuum to 30 microns.

15. Pull the unit down and check to make sure all joints aretight and leak free. Open the discharge line service valve.See Fig. 6.

16. Open the liquid line service valve. See Fig. 6.

17. Follow the unit's start-up instructions.

NOTE: Accessory items need to be installed before theducts are attached.

Unit Discharge Units are shipped from the factoryconfigured for vertical discharge. The units (except the50BYN014) can be converted to front or horizontal discharge

by following these instructions:

1. Remove the screws (8) from the top front access panel togain access to the fan section.

2. Loosen the supply fan mounting bolts (4) and slide thefan motor back until the belts (3) are loose.

3. Remove the belts (3).

4. Remove the screws (8) from the unit top panel that holdsthe fan.

5. Remove the top cover and fan.

6. Position fan where the top front access panel was mounted.

7. Secure the fan with the screws removed in Step 1.

8. Re-mount the belts.

NOTE: Some units require different belts for different fanset ups. If this is the case, new belts are provided inside thefan enclosure.

9. Slide the fan motor back until the proper belt tension isobtained. Secure the motor with the mounting bolts (4).

10. Mount front access cover on top of the unit (where the topcover was originally) and secure with the screws (8) re-moved in Step 4.

Vibration Isolation Unit compressors are internallyisolated and the compressor compartment is lined with acousti-cal insulation. If additional vibration isolation is desired, rubberpads may be located under each unit corner or unit may bemounted on rubber shear isolators. Spring isolators are not nor-mally required. Ductwork attached to the unit should be isolated

from the unit with a flexible collar on the inlet and outlet ducts.Step 3 Install Accessories (If Required) Refer to the following and the instructions provided with theindividual accessory. Refer to Fig. 8 for typical system set up.

HEATING COILS Accessory steam or hot water heatingcoils are mounted in the unit return air before the cooling coil.

1. Remove the filter rack provided with the unit.

2. Mount the filter rack on the coil.

3. Mount the coil in the position where the filter rack was.

NOTE: The filter rack may be used with either ducted orfree air return set ups. Make sure adequate air mixing occursto prevent coil freeze-up. A 50BB900---001 freeze protec-tion thermostat is recommended.

LOW AMBIENT KIT If the unit will be operated withinlet air to the condenser below 50 F, a head pressure controllow-ambient damper may be required. The low-ambient kitcontrols head pressure by discharge dampers on the condenserfan. The dampers are actuated by a refrigerant-operated pistonconnected to the discharge line of the condenser. If a low-ambient accessory will be used, install it at this time (beforefinal ductwork connections are made).

INLET FILTER KIT An accessory filter rack may also beinstalled on the air inlet to help keep the coil clean. This filterrack should be installed before the ductwork is attached to theunit (if required in your specific application).

Refer to installation instructions provided with the accesso-ries for installation details.

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Fig.1

BaseUnitDimensions

50BYN006-014

DIMENSIONALCHART

CORNERWEIGHTS

50BY

006

008

012

014

DIM

mm

ft-in.

mm

ft-in.

mm

ft-in.

mm

ft-in.

A

1800

5-105/8

1800

5-105/8

1780

5-10

1780

5-10

B

1040

3-5

1231

4-01/2

1613

5-31/2

1804

5-11

C

690

2-31/8

690

2-31/8

745

2-53/8

745

2-53/8

D

765

2-61/8

765

2-61/8

825

2-81/2

825

2-81/2

E

355

1-2

420

1-41/2

608

2-0

675

2-25/8

F

170

0-63/4

158

0-61/4

191

0-71/2

193

0-75/8

G

320

1-05/8

357

1-2

402

1-37/8

452

1-53/4

H

310

1-01/4

350

1-13/4

372

1-25/8

424

1-43/4

J

593

1-113/8

593

1-113/8

665

2-21/4

665

2-21/4

K

554

1-97/8

554

1-97/8

457

1-6

457

1-6

L

584

1-11

584

1-11

584

1-11

584

1-11

M

23

0-07/8

23

0-07/8

23

0-07/8

23

0-07/8

N

17

0-05/8

17

0-05/8

17

0-05/8

17

0-05/8

P

11.5

0-01/2

11.5

0-01/2

11.5

0-01/2

11.5

0-01/2

Q

43

0-13/4

43

0-13/4

43

0-13/4

43

0-13/4

R

605

1-113/4

605

1-113/4

605

1-113/4

605

1-113/4

S

50

0-2

55

0-21/8

55

0-21/8

55

0-21/8

T

360

1-21/8

400

1-33/4

357

1-2

357

1-2

V

50

0-2

20

0-07/8

24

0-1

24

0-1

W

660

2-2

660

2-2

660

2-2

660

2-2

X

535

1-91/8

535

1-91/8

590

1-111/4

590

1-111/4

Y

190

0-71/2

190

0-71/2

190

0-71/2

190

0-71/2

Z

124

0-47/8

124

0-47/8

124

0-47/8

124

0-47/8

AA

475

1-63/4

475

1-63/4

475

1-63/4

475

1-63/4

AB

140

0-51/2

140

0-51/2

140

0-51/2

140

0-51/2

AC

60

0-23/8

60

0-23/8

60

0-23/8

60

0-23/8

AD

21

0-07/8

21

0-07/8

21

0-07/8

21

0-07/8

AE

225

0-87/8

225

0-87/8

217

0-81/2

217

0-81/2

AF

155

0-61/8

155

0-61/8

155

0-61/8

155

0-61/8

AG

190

0-71/2

190

0-71/2

190

0-71/2

190

0-71/2

AH

73

0-27/8

61

0-23/8

59

0-23/8

59

0-23/8

AJ

895

2-111/4

1110

3-93/4

1495

4-107/8

1686

5-63/8

AK

386

1-31/4

405

1-4

260

0-105/8

356

1-2

AL

433

1-5

480

1-67/8

433

1-5

433

1-5

AM

275

0-107/8

275

0-107/8

AN

433

1-5

433

1-5

AP

80

0-31/8

80

0-31/8

80

0-31/8

80

0-31/8

AQ

880

2-105/8

1070

3-61/8

1455

4-91/4

1645

5-43/4

AR

41

0-15/8

41

0-15/8

41

0-15/8

41

0-15/8

AS

533

1-9

605

1-117/8

807

2-73/4

920

3-01/4

AT

347

1-15/8

355

1-2

375

1-23/4

395

1-31/2

AV

50

0-2

50

0-2

50

0-2

50

0-2

AW

231

0-91/8

231

0-91/8

169

0-61/2

169

0-61/2

CORN

ERWEIGHTS

50BY

006

008

012

014

CORNER

kg

lb

kg

lb

kg

lb

kg

lb

A

65.3

144

84

185

107

236

108

238

B

68.5

151

81

179

107

236

113

248

C

69.4

153

89

136

108

239

127

280

D

65.8

145

92

203

108

239

119

263

NOTES:

1.

Dimensionsin[]areinmillimeters.

2.

Centerofgravity.

3.

Directionofairflow.

4.

Onesideofunitmusthaveminimumof3

[914]

clearanceforfilter

removal.

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Fig.2B

aseUnitDimensions

50BYN0

16

DIMENSIONALCHART

DIM

UNIT50BY016

mm

ft-in.

A

1980

6-6

B

1905

6-3

C

745

2-53/8

D

825

2-81/2

E

543

1-93/8

F

257

0-101/8

G

356

1-2

H

353

1-17/8

J

665

2-21/4

K

635

2-1

L

597

1-111/2

M

19

0-03/4

N

17

0-05/8

P

17

0-05/8

Q

43

0-13/4

R

607

1-117/8

S

84

0-33/8

T

402

1-37/8

V

22

0-07/8

W

765

2-61/8

X

603

1-113/4

Y

190

0-71/2

Z

124

0-47/8

AA

432

1-5

AB

83

0-31/4

AC

60

0-23/8

AD

21

0-07/8

AE

217

0-81/2

AF

141

0-51/2

AG

190

0-71/2

AH

86

0-33/8

AJ

1737

5-83/8

AK

318

1-01/2

AL

483

1-7

AM

311

1-01/4

AN

483

1-7

AP

70

0-23/4

AQ

1765

5-91/2

AR

41

0-15/8

AS

979

3-21/2

AT

385

1-31/8

AV

276

0-107/8

AW

169

0-61/2

AX

50

0-2

CORNERWEIGHTS

UNIT50BY016

kg

lb

A

119

263

B

142

312

C

152

334

D

128

281

NOTES:

1.


2.

Centerofgravity.

3.

Directionofairflow.

4.

Onesideofunitmusthaveminimumof3

[914

]clearanceforfilter

removal.

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Fig.3B

aseUnitDimensions

50BYN0

24

CORNERWEIGHTS

CORNER

50BYN024

kg

lb

A

183

403

B

194

428

C

192

424

D

181

400

DIMENSIONALCHART

DIM

50BYN024

mm

ft-in.

A

2341

7-81/4

B

2108

6-11

C

794

2-71/4

D

872

2-103/8

E

581

1-107/8

F

184

0-71/4

G

406

1-4

H

379

1-3

J

830

2-85/8

K

796

2-71/4

L

584

1-11

M

28

0-11/8

N

40

0-15/8

P

51

0-2

Q

43

0-13/4

R

805

2-73/4

S

65

0-21/2

T

457

1-6

V

16

0-05/8

W

921

3-01/4

X

610

2-0

Y

202

0-8

Z

86

0-33/8

AA

422

1-45/8

AB

140

0-51/2

AC

60

0-23/8

AD

21

0-07/8

AE

226

0-87/8

AF

184

0-71/4

AG

220

0-83/4

AH

62

0-21/2

AJ

1984

6-61/8

AK

345

1-15/8

AL

530

1-87/8

AM

356

1-2

AN

530

1-87/8

AP

76

0-3

AQ

1956

6-5

AR

41

0-15/8

AS

1085

3-63/4

AT

399

1-33/4

AV

314

1-03/8

AW

236

0-91/4

AX

50

0-2

AY

1471

4-10

NOTES:

1.


2.

Centerofgravity.

3.

Directionofairflow.

4.

Onesideofunitmusthaveminimumof

3

[914]clearanceforfilter

removal.

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Table 1 Physical Data

LEGEND

*The 20 ton unit is factory wired for 2 stages of capacity control. With the addition of a3-stage thermostat or outdoor-air thermostat, the unit is capable of 3 stages of capacitycontrol.

Shaft center distances shown are for vertical discharge arrangement.**Shaft center distances shown are for horizontal discharge arrangement.

UNIT 50BYN 006 008 012 014 016 024

NOMINAL CAPACITY (tons) 5 71/2 10 12 15 20

UNIT OPERATING WEIGHT (lb) 594 765 948 1036 1190 1654

COMPRESSOR Carrier ScrollModel SR58 SR75 SR58 SR58/SR75 SR75 SR75Quantity 1 1 2 1/1 2 3Rpm 3500Oil Charge (oz) 44 50 44/44 50/44 50/50 50/50/50Steps of Control 1 1 2 2 2 2*

OPERATING CHARGE R-22 (lb) 8.6 10.1 8.0/8.8 8.8/10.6 9.9/9.9 9.9/9.9/9.9

EVAPORATOR FAN Adjustable, Belt-Driven, CentrifugalNominal Cfm 2000 3000 4000 4800 6000 8000Cfm Range 1,500-2,500 2,250-3,750 3,000-5,000 3,750-6,250 4,500-7,500 6,000-10,000Available Static 1.2 1.25 2.25 2.25 2.0 2.0Fan Size 101/2 x 71/2 11 x 8 121/2 x 91/2 14 x 12 121/2 x 91/2 121/2 x 91/2Number of Fans 1 1 1 1 2 2Standard Speed Range (Rpm) 1058-1449 950-1300 860-1120 849-1117 1045-1308 930-1160Max Allowable Rpm 1900 1700 1500 1360 1900 1600Motor Rpm 1725Vertical Belt Quantity...Type 1...A33 1...A34 1...B41 1...B45 2...A42 2...B52Horizontal Belt Quantity Type 1...A24 1...A24 1...B39 None 2...A32 2...B40Fan Pulley (in.) 41/4 43/4 85/8 85/8 65/8 71/2Motor Pulley (in.) 21/2-31/2 21/2-31/2 41/8-51/2 41/8-51/2 4-5 4-5Nominal Hp...Frame Size 11/2...145T 2...145T 3...182T 5...184T 5...184T 71/2...184TFan Shaft Size (mm) 20 20 20 20 25 25Motor Shaft Size (in.) 7/8 7/8 11/8 11/8 11/8 11/8Center Distance (in.) min/max 13.6-13.8 13.2-13.4 10.4-11.9 9.6-10.6 12.2-13.7 17.6-18.7Center Distance (in.) min/max.** 6.6-7.7 6.4-7.4 N/A N/A 7-8 10.6-11.4

EVAPORATOR COIL 3/8

-in. OD, Enhanced Copper Tube, Aluminum FinsQuantity Rows...Fin/in. 3...14 4...14 4...14 4...14 4...14 4...15Face Area (sq ft) 5.7 7.0 9.5 10.8 12.2 17.6

RETURN AIR FILTERS 1 or 2 in. Disposable Type

Quantity...Size1...16 x 25 1...25 x 25 3...20 x 25 3...16 x 25 2...25 x 25 8...16 x 201...20 x 25 1...20 x 25 1...20 x 25 1...20 x 25

CONDENSER FAN Adjustable, Belt-Driven, CentrifugalNominal Cfm 3000 4500 6000 7200 9000 12,000Cfm Range 2,250-3,750 3,375-5,625 4,500-7,500 5,400-9,000 6,750-11,250 9,000-15,000Available Static 1.0 1.0 1.0 1.0 1.0 1.0Fan Size 11 x 11 121/2 x 121/2 11 x 11 11 x 11 121/2 x 1 21/2 14 x 14Number of Fans 1 1 2 2 2 2Standard Speed Range (Rpm) 952-1304 849-1117 1038-1305 1038-1305 903-1136 930-1150Max Allowable Rpm 1700 1500 1700 1700 1500 1360

Motor Rpm 1725Belt Quantity...Type 1...A65 1...B68 2...A67 2...A67 2...A78 2...B85Fan Pulley (in.) 5 81/2 63/4 63/4 73/4 73/4Motor Pulley (in.) 21/2-31/2 41/2-51/2 4-5 4-5 4-5 4-5Nominal Hp...Frame Size 2...145T 3...182T 5...184T 5...184T 5...184T 71/2...184TFan Shaft Size (mm) 20 20 25 25 25 25Motor Shaft Size (in.) 7/8 11/8 11/8 11/8 11/8 11/8Center Distance (in.) min/max 26.7-27.4 23.1-24.2 24.7-26.2 25.0-26.2 28.9-30.5 34.5-35.9

CONDENSER COIL 3/8-in. OD, Enhanced Copper Tube, Aluminum FinsQuantity Rows...Fins/in. 4...14 4...14 5...14 5...14 5...14 5...15Face Area (sq ft) 6.4 7.7 10.5 11.8 14.2 19.4

CONTROLS 24 Volts Provided in UnitHigh Pressure Cutout (psig) 395

Cut-in (psig) 300Low Pressure Cutout (psig) 27

Cut-in (psig) 67Fusible Plug 203 FTime Guard II Devices 5 Minutes on Each Circuit

CONDENSATE DRAIN LINE 2 @ 3/4 BPS

N PT National Pipe ThreadBPS British Pipe Standard

(NPT pipe will work with the type of fitting)

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Step 4 Install Ductwork The 50BYN unit is de-signed for use either with or without ductwork or rain louvers.If either is used, care must be taken to eliminate air recircula-tion. Recirculation can be minimized by discharging throughan extension elbow. When properly designed, single deflectiondischarge louvers can be applied to ductwork and to the unit airdischarge. Fixed rain louvers over discharge outlets can causeexcessive recirculation and nuisance high-pressure switch cut-outs. Obstructions closer than 10 ft to the discharge air patterncan also cause significant recirculation.

NOTE: See Fig. 9 for recommended duct sizing

The 50BYN016 and 024 units are shipped with the con-denser flanges stored inside the condenser section. Beforeattaching ductwork, mount the flanges to the condenser asshown in Fig. 10.

CONDENSER AIR DUCT The condenser supply and dis-charge air duct should be as short and straight as possible. Thecross section area of the duct should never be less than the facearea of the unit openings. Ductwork should be insulated to pre-vent moisture condensation on the unit panels during coldweather. (See Fig. 11.)

Insulate as follows:

1. If metal ductwork is used, insulation may be appliedon the inside of the duct. This installation should be ex-tended to cover the inside of the duct flanges. It is neces-

sary to insulate the inside of the ducts at the duct flangesto reduce heat loss from the metal cabinet by conductionthrough the duct flanges and into the cold duct. Interiorinsulation allows the metal duct to approach room tem-perature. It also prevents condensation from forming andcollecting under the insulation which will occur withexterior duct insulation.

NOTE: Fiberglass duct board may also be used if permittedby local codes.

2. If insulation is applied to the outside of the metal duct, theinside must be insulated for a length of 10 in. from theunit (including the duct flanges) or up to the flexible ductvapor barrier on the outside, which must be tightly sealedto prevent condensation under the insulation.

SPREADER BAR

SUPPORTSUNDER SKID

Fig. 4 50BYN Unit Rigging

SERVICEVALVE

Fig. 5 50BYN024 Unit (Service Panels Removed)

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THREADED LIQUID LINEFITTING ON TXV(3 CIRCUITS)

THREADEDSUCTION CONNECTION(3 CIRCUITS)

LIQUID LINETHREADEDCONNECTIONSAND SERVICEVALVES(3 CIRCUITS)

SUCTION LINESERVICE PORT

DISCHARGE LINESERVICE VALVE

DISCHARGE LINESERVICE PORT

UNITS SPLITAT THIS POINT

Fig. 6 50BYN024 Front View

Fig. 7 Splitting the 50BYN024 Unit

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FILTER DRIER

SERVICEVALVE

LIQUID LINE

THREADEDCONNECTION

COMP

SERVICEVALVE

THREADEDCONNECTION

SERVICEPORT

DISCHARGE LINE

SERVICEPORT

THREADEDCONNECTION

TXVSUCTION LINE

COND

EVAP

Fig. 8 Typical System Setup

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*

INLETLOUVER

F

B

D

C

4 3/4" 1"

50BYN

A

DISCHARGELOUVER

50BYN

G

45

55/8

"

4"

4"

14 GAGE ALUMINUM OR18 GAGE GALVANIZED STEEL

FLANGENOT PERMISSIBLE

BLADE STIFFENERFOR LOUVER WIDTHSOVER 30"

5"

3"1/2"

4"

1"

30

EXHAUST

VANE DEFLECTOR

CONDENSER INTAKE

Fig. 9 Typical Recommended Condenser Duct Dimensions

*Access panel for condenser coil cleaning.

INLET LOUVER DETAIL DISCHARGE LOUVER DETAIL

DEFLECTOR DETAIL

DIMENSIONS (in.)

UNIT50BYN

A B C D F G

006 24 141/8 6 201/8 26 345/8

008 24 153/4 6 213/4 26 411/8

012 24 14 6 20 26 571/4

014 24 14 6 20 26 643

/4016 30 157/8 6 217/8 301/8 691/2

024 30 18 6 24 361/4 78

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CONDENSER AIRFLOW LOUVERS The proximity ofthe condenser air inlet and discharge airstreams makes the pos-sibility of air recirculation quite high. It is possible to use onelouver to route inlet and discharge airstreams but it is notrecommended.

Separate inlet and discharge louvers are recommended (seeFig. 9) to avoid air leakage from discharge to inlet. A bafflemay also be used on the outside of the building to direct dis-charge away from the air inlet.

Louvers should be selected with sufficiently strong bladesfor the application. Louver blades should be at least 30-in. wide

and constructed of a minimum of 18-gage metal.EVAPORATOR DUCTWORK Supply duct should beproperly supported and the aspect ratio as close to square aspossible. Duct should be sized for a maximum of 2000 feet perminute velocity in areas outside the equipment room. The ductshould be lined with acoustical insulation for a minimum of10 ft beyond the equipment room. A flexible duct connectionshould be used on the connection to the unit to prevent trans-mission of any unit vibrations into the duct.

Return duct may be attached to the unit, but is not necessary.The return to the unit should prevent line of sight visibility tothe space. Insulated return duct is also recommended for acous-tically sensitive spaces. Maximum velocity should not exceed1000 ft per minute over occupied spaces. Adequate return areais essential for proper operation.

Step 5 Install Rain/Condensate Drain Line

The 50BYN unit has a drain connection for evaporatocondensate and a connection on the unit base to drain any rainwater that may accumulate. Rain drain connection can be madeon either side of the unit. Block whichever drain is not beingused, but DO NOT BLOCK BOTH drain locations.When con-necting rain drains and condensate drains from the unit to floor

drains, sinks, or hoppers, connect drains downstream of trap toensure that condensate does not drain back into the unit.

A drain kit is provided (shipped in the fan section). Thiskit consists of PVC drain fittings to adapt to field-suppliedthreaded pipe. Make connections through the unit side panelSome applications may require connection to either galvanizedsteel or copper drain pipe; consult local code requirements fodetails.

Pitch drain pipe downward at a slope of at least 1/4-in. per ffor proper drainage. Provide tees plugged on one side focleanouts. Leave clearance for servicing, and observe all localsanitary codes.

The condensate trap should have a depth adequate to allow3-in. of water in the trap (see Fig. 12) with the unit running.

IMPORTANT: A rain drain connection MUST BEUSED if any possibility exists of rain water enteringthe unit.

IMPORTANT: NEVER use pipe smaller than 3/4 inchesin the drain run.

DUCT FLANGE

Fig. 10 Placement of Duct Flanges (50BY016,024)

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*Provide access for cleaning condenser coil.

Fig. 11 50BYN Applications

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Step 6 Complete Electrical Connections

GENERAL Verify that nameplate electrical requirementsmatch available power supply. Voltage at condenser must bewithin the minimum and maximum shown in Table 2 and phas-es must be balanced within 2%. Contact local power companyfor line voltage corrections. Never operate a motor where aphase imbalance in supply voltage is greater than 2%.

Use the following formula to determine the percentage of

voltage imbalance:UNBALANCED 3-PHASE SUPPLY VOLTAGE Usethe following formula to determine the percent of voltageimbalance.

Percent Voltage Imbalance

Example: Supply voltage is 460-3-60.

AB = 452 vBC = 464 vAC = 455 v

Determine maximum deviation from average voltage:

(AB) 457 452 = 5 v(BC) 464 457 = 7 v(AC) 457 455 = 2 v

Maximum deviation is 7 v.

Determine percent of voltage imbalance:

% Voltage Imbalance = 100 x

= 1.53%

This amount of phase imbalance is satisfactory as it is be-low the maximum allowable 2%.

Unit operation on improper line voltage or excessive phaseimbalance may be considered abuse and any resulting damagemay not be covered by Carrier warranty.

All wiring must be in accordance with local or NEC(National Electrical Code) regulations.

POWER WIRING The units must have adequate overcur-rent protection, fuses, or HACR (Heating, Air Conditioningand Refrigeration) breakers, according to the national and ap-plicable local codes.

For field power connections, all main power wiring entersthe unit through a factory-punched access hole under the control box. Attach power wires to the power connections on themain power terminal block in the unit control box. Be sure toinstall a ground wire.

CONTROL WIRING All units require an accessory ther-mostat package to complete the unit control system. Any of thefollowing controls systems can be used:

1. Room-mounted thermostat. Thermostat may be mountedin an appropriate location in the conditioned space. Routethe wires from the thermostat to the low voltage connection of the control box. Connect wires to the low voltageterminal block. The fan switch on the thermostat will control fan operations.

2. Carrier TEMP thermostat. Mount relay pack for theCarrier TEMP thermostat in the low voltage section of thecontrol box. Wire from the relay pack to the low voltageterminal strip and from the relay pack to the thermostat.

FREEZE PROTECTION THERMOSTAT An accessoryfreeze protection thermostat is required when a liquid line lossof-charge switch is installed or when the unit is equipped withan airside economizer for intermediate or cold weather opera-tion. Refer to Fig. 13 and 14 and the installation instructionsincluded with the thermostat. Field installation of an evaporatofreeze-up thermostat (50BB900001) is required.

WINTER START MODIFICATIONS When starting aircooled units under low-ambient temperature conditions, thecompressor may pull suction pressure down below the lowpressure cutout switch setting causing the compressor to shut offAt extremely low temperatures, the low-pressure switch mayopen during the off cycle, preventing the compressor from starting. In these cases, winter start control is required as follows:

If 50BZ unit has a low-pressure switch, the use of the winterstart kit (part no. CRWINSTR01A00) is recommended. This kibypasses the low-pressure switch on start-up.

START-UP

General Complete the start up checklist on page CL-1before attempting system start-up.

1. Set indoor thermostat system switch to OFF position

and fan switch to AUTO position.

2. Check all electrical connections, fuses, starter and pressure control resets.

3. Check operation of evaporator fan motor and ensure fanrotation is correct. If rotation needs to be reversed, dis-connect main power and switch any 2 leads on the loadside of the disconnect switch.

4. Adjust fan speed. Units are belt-driven condenser unitand allow for a wide range of inlet static and condenserairflow requirements. It may be necessary to adjust thecondenser airflow to account for these inlet conditionsInadequate airflow will result in poor unit performanceand possible nuisance tripping of high-pressure switchesIf an airflow is not specified, use the nominal airflowfrom Tables 3 and 4 and adjust the fan speed to compensate for actual job conditions. Use Table 1 to determineproper fan speed. If the unit trips on high pressure due tohigh condensing temperature it may be necessary to in-crease the fan speed and condenser airflow.

5. The outdoor-air fans cycle with the compressor Be surefans are running during compressor rotation.

= 100 xmax voltage deviation from average voltage

average voltage

Average Voltage =452 + 464 + 455

3

=1371

3

= 457

IMPORTANT: If supply voltage phase imbalance ismore than 2%, contact your local electric utility com-pany immediately.

7457

To prevent injury, ensure that ducting or wire fan guardsare installed on the condenser fan before starting the unit.

TO UNIT

DRAINPLUG

MINIMUM PITCHONE IN. PER10 FT. OF LINE

OPENVENT

SEENOTE

Fig. 12 External Trap Condensate Drain

NOTE: Trap should be deep enough to offset maximum unit staticdifference. A 4-in. trap is recommended.

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Table 2 Electrical Data

LEGEND

*Minimum Ckt Amps and MOCP Amps values per NEC (see Note 1).The overcurrent protective device for the unit shall be fuse or HACR circuit breaker (see Note 1).

NOTES:1. In compliance with NEC requirements for multimotor and combination load equipment

(NEC Articles 430 and 440), the overcurrent protective device for the unit shall be fuseor HACR circuit breaker. Canadian units may be fuse or circuit breaker.

2. Wire sizing amps are a sum of 125% of the compressor RLA plus 100% of indoor fanmotor FLA.

3. Motors are protected against primary single phasing condition.4. Indoor-fan motors are 3-phase motors of same voltage as unit.

UNIT50BYN

V-PH-Hz

VOLTAGERANGE

COMPRESSORNO. 1

COMPRESSORNO. 2

COMPRESSORNO. 3

CONDENSERFAN

INDOOR-FANMOTOR

POWERSUPPLY*

Min Max RLA LRA RLA LRA RLA FLA Hp FLA Hp FLA MCA MOCP

006

208/230-3-60 187 253 18.3 125 2.0 7.5 1.5 6.6 37.0 50

460-3-60 414 506 9.2 67 2.0 3.4 1.5 3.0 17.8 25

575-3-60 518 632 7.3 27 2.0 2.7 1.5 2.4 14.3 20

008

208/230-3-60 187 253 20.4 146 3.0 10.6 2.0 7.5 43.6 60

460-3-60 414 506 10.2 73 3.0 4.8 2.0 3.4 21.0 30

575-3-60 518 632 8.2 50 3.0 3.9 2.0 2.7 16.8 20

012208/230-3-60 187 253 17.7 125 17.7 125 5.0 16.7 3.0 10.6 67.1 80

460-3-60 414 506 8.9 67 8.9 67 5.0 7.6 3.0 4.8 32.3 40

575-3-60 518 632 7.1 27 7.1 27 5.0 6.1 3.0 3.9 25.9 30

014

208/230-3-60 187 253 17.7 125 20.9 146 5.0 16.7 5.0 16.7 76.4 90

460-3-60 414 506 8.9 67 10.5 73 5.0 7.6 5.0 7.6 36.7 45

575-3-60 518 632 7.1 27 8.4 50 5.0 6.1 5.0 6.1 29.4 35

016

208/230-3-60 187 253 20.9 146 20.9 146 5.0 16.7 5.0 16.7 80.4 100

460-3-60 414 506 10.5 73 10.5 73 5.0 7.6 5.0 7.6 38.7 45

575-3-60 518 632 8.4 50 8.4 50 5.0 6.1 5.0 6.1 31.0 35

024

208/230-3-60 187 253 20.9 146 20.9 146 20.1 146 7.5 24.2 7.5 24.2 116.8 125

460-3-60 414 506 10.5 73 9.9 73 9.5 73 7.5 11.0 7.5 11.0 56.0 60

575-3-60 518 632 8.4 50 8.4 50 8.4 50 7.5 9.0 7.5 9.0 45.2 50

FLA Full Load AmpsLRA Locked Rotor AmpsMCA Minimum Circuit AmpsMOCP Maximum Overcurrent Protective

Device (see Note 1)NEC National Electrical CodeRLA Rated Load Amps

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W1

Y1

G

W3

CK1

CK2

R

C

W2

Y2

RS2

RS+5

RS1

RS GND

UNITGROUND

33CS250-01

R

G

T1

Y1

X

C

Y2

TB2

T2

50BYN

(012 SIZE UNIT AND LARGER)

WIRE NUT

SHIELD (CUT ANDTAPE BACK)

REMOTEROOMSENSOR(P/N ZONECCORRS01)

O/W2

Y1

R

G

Y/Y2

W/W1

C

B

L

DO NOT USE

S1

S2

33CSPTN-01

R

G

T1

Y1

X

C

Y2

TB2

T2

50BYN

(012 SIZE UNITAND LARGER)

WIRE NUT

SHIELD (CUT ANDTAPE BACK)

REMOTEROOMSENSOR(P/N ZONECCORRS01)

UNITGROUND

NOTE: Remote sensor is field-installed option.

Fig. 13 Thermostat Connection Diagram with 33CS250-01 Thermostat

NOTE: Remote sensor is field-installed option.

Fig. 14 Thermostat Connection Diagram with 33CSPTN-01 Thermostat

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Table 3 Condenser Fan Performance

LEGEND

Shaded areas require field-supplied drive.

50BYN

STATIC PRESSURE (in. wg)

Cfm0.0 0.2 0.4 0.6 0.8 1.0

Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp

006

2,000 566 0.18 710 0.30 846 0.40 972 0.46 1070 0.61 1130 0.72

2,500 753 0.40 880 0.59 927 0.63 1020 0.79 1105 1.10 1184 1.35

3,000 940 0.83 985 0.90 1080 1.00 1122 1.10 1200 1.29 1320 1.46

3,500 1047 1.20 1140 1.47 1173 1.50 1250 1.70 1292 1.40 1360 1.59

4,000 1250 1.94 1257 2.00 1333 2.10 1390 2.41 1410 2.60 1470 2.76

008

3,000 547 0.30 670 0.54 751 0.60 840 0.80 920 1.10 995 1.50

3,750 760 0.89 824 1.10 920 1.25 964 1.30 1040 1.53 1110 2.10

4,500 910 1.53 940 1.70 1020 1.90 1090 2.08 1173 2.40 1240 2.59

5,250 1020 2.00 1095 2.40 1170 2.90 1180 3.00 1240 3.10 1300 3.53

6,000 1180 3.10 1195 3.20 1260 3.70 1320 4.16 1380 4.80 1440 5.60

012

4,000 665 0.40 803 0.65 920 0.97 989 1.20 1080 1.48 1163 1.90

5,000 830 0.82 912 1.20 1010 1.55 1088 1.70 1170 2.00 1246 2.50

6,000 976 1.70 1070 2.16 1131 2.30 1210 2.66 1318 2.90 1390 3.36

7,000 1120 2.85 1198 3.00 1273 3.20 1343 3.70 1410 4.21 1474 4.90

8,000 1282 3.90 1353 4.50 1420 5.06 1517 5.30 1580 5.93 1640 6.70

014

4,800 703 0.62 840 1.05 860 1.10 950 1.29 1090 1.62 1172 2.02

6,000 853 1.12 902 1.60 1060 2.10 1130 2.30 1210 2.66 1290 3.20

7,200 1045 2.40 1140 3.00 1191 3.20 1270 3.62 1290 3.79 1357 4.60

8,400 1190 3.60 1270 4.20 1340 4.89 1421 5.10 1490 5.85 1560 6.70

9,600 1380 5.70 1452 6.50 1520 7.13 1550 7.20 1611 7.50 1670 8.23

016

6,000 600 0.60 720 1.02 820 1.51 910 2.10 950 2.20 1025 2.80

7,500 736 1.50 833 1.86 920 2.50 1015 2.80 1040 3.08 1106 3.80

9,000 942 3.20 1030 3.60 1040 4.20 1110 4.50 1141 4.80 1230 5.03

10,500 1075 5.10 1150 6.25 1220 6.80 1280 6.72 1340 7.50 1400 8.50

12,000 1230 7.10 1310 8.20 1350 8.96 1410 9.20 1465 9.80 1470 10.10

024

8,000 560 1.68 640 2.04 705 2.40 770 3.00 850 3.60 920 3.98

10,000 710 3.36 760 3.72 820 4.20 870 4.80 930 5.40 975 6.00

12,000 845 5.28 890 5.70 945 6.20 975 6.71 1025 7.26 1090 7.70

14,000 960 8.14 1020 8.80 1076 9.24 1090 9.90 1125 10.50 1150 11.00

16,000 1090 11.60 1150 12.50 1190 12.80 1200 13.20 1230 13.70 1250 14.00

Bhp Brake Horsepower

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Table 4 Evaporator Fan Performance

LEGEND

1. Shaded areas require field-supplied drive.

2. Italics require field-supplied motor.

CFMEXTERNAL STATIC PRESSURE (in. wg)

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2

50BYN006

1500Rpm 690 860 978 1100 1210 1310 1400

Bhp 0.20 0.30 0.35 0.47 0.44 0.56 0.69

1750Rpm 800 950 1080 1140 1240 1340 1430

Bhp 0.22 0.36 0.53 0.60 0.68 0.90 1.10

2000Rpm 953 1090 1140 1240 1340 1430 1520

Bhp 0.44 0.61 0.65 0.80 0.86 1.04 1.23

2250Rpm 1040 1160 1270 1340 1430 1480 1550

Bhp 0.58 0.80 0.97 1.10 1.23 1.30 1.33

2500Rpm 1209 1324 1430 1460 1550 1640 1720

Bhp 0.84 1.10 0.38 1.40 1.56 1.85 2.13

50BYN008

2250Rpm 683 827 950 980 1100 1130 1180

Bhp 0.24 0.43 0.66 0.73 0.76 0.83 0.94

2625Rpm 845 980 990 1100 1150 1220 1320

Bhp 0.57 0.83 0.88 1.03 1.18 1.23 1.32

3000Rpm 930 1046 1150 1210 1270 1340 1500

Bhp 0.71 1.01 1.34 1.37 1.59 1.64 1.94

3375Rpm 1060 1172 1270 1350 1380 1400 1505

Bhp 1.07 1.42 1.81 1.91 2.04 2.13 2.29

3750Rpm 1250 1350 1370 1390 1440 1520 1550

Bhp 1.72 2.10 2.27 2.37 2.63 2.70 2.89

50BYN012

3000Rpm 710 790 870 930 980 1060 1100 1180 1240 1290 1390 1400

Bhp 0.66 0.77 0.91 0.97 1.14 1.23 1.38 1.44 1.67 1.88 2.04 1.99

3500Rpm 720 820 920 920 1050 1120 1190 1240 1280 1320 1400 1410

Bhp 0.70 0.86 1.21 1.40 1.65 1.69 1.98 1.98 2.17 2.33 2.50 2.45

4000Rpm 852 960 1050 1090 1180 1200 1240 1320 1330 1440 1410 1420

Bhp 0.95 1.35 1.80 2.02 2.28 2.40 2.30 2.60 2.70 2.80 2.90 2.96

4500Rpm 946 1042 1130 1210 1220 1320 1330 1340 1420 1430 1500 1550

Bhp 1.32 1.76 2.25 2.76 2.83 3.10 3.20 3.34 3.45 3.53 4.07 4.49

5000Rpm 1040 1125 1205 1280 1320 1340 1430 1470 1500 1520 1580 1610

Bhp 1.75 2.22 2.73 3.21 3.40 3.75 3.97 4.41 4.68 4.87 4.76 5.03


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Table 4 Evaporator Fan Performance (cont)

LEGEND

1. Shaded areas require field-supplied drive.

2. Italics require field-supplied motor.

CFMEXTERNAL STATIC PRESSURE (in. wg)

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2

50BYN014

3,600Rpm 580 640 710 780 845 910 975 1040 1080 1130 1180 1280

Bhp 0.67 0.80 0.94 1.06 1.25 1.49 1.63 1.76 1.97 2.30 2.50 2.70

4,200Rpm 670 730 760 900 915 935 1040 1050 1100 1150 1215 1285

Bhp 1.03 1.18 1.40 1.63 1.72 1.83 2.13 2.20 2.34 2.70 2.80 3.30

4,800Rpm 760 840 850 930 940 1035 1060 1090 1130 1205 1280 1330

Bhp 1.50 1.79 1.86 2.12 2.15 2.48 2.67 2.80 2.95 3.30 3.70 3.80

5,400Rpm 850 880 955 1005 1050 1060 1115 1160 1205 1270 1340 1360

Bhp 2.10 2.40 2.64 2.87 3.05 3.14 3.40 3.70 3.92 4.35 4.56 4.76

6,000Rpm 955 980 1035 1060 1110 1150 1170 1220 1240 1285 1360 1380

Bhp 2.98 3.22 3.35 3.60 3.80 4.00 4.22 4.40 4.60 4.75 5.60 5.80

50BYN016

4,500Rpm 676 840 970 940 1037 1092 1170 1251 1320 1370 1432 1462

Bhp 0.60 1.04 1.35 1.50 1.60 1.72 1.80 1.85 1.90 2.54 2.90 3.20

5,250Rpm 731 865 980 1083 1100 1180 1210 1280 1370 1434 1490 1550

Bhp 0.80 1.20 1.65 2.00 2.20 2.35 2.47 2.70 2.98 3.42 3.50 3.67

6,000Rpm 891 1020 1134 1140 1217 1240 1313 1327 1400 1450 1514 1580

Bhp 1.44 2.16 2.80 2.90 3.00 3.18 3.40 3.50 3.70 4.25 4.50 4.80

6,750Rpm 950 1060 1160 1240 1280 1350 1390 1450 1514 1540 1590 1640

Bhp 1.80 2.50 3.18 3.70 3.80 4.10 4.30 4.70 5.10 5.30 5.90 6.30

7,500Rpm 1060 1160 1290 1330 1350 1420 1488 1540 1600 1650 1707 1760

Bhp 2.50 3.27 4.37 4.50 4.70 5.02 5.40 5.68 6.20 6.50 6.90 7.40

50BYN024

6,000Rpm 670 786 890 915 990 1090 1120 1180 1270 1310 1360 1470

Bhp 0.85 1.32 1.92 2.10 2.31 2.64 2.86 3.30 3.49 4.00 4.30 4.60

7,000Rpm 820 930 980 1035 1070 1140 1225 1270 1290 1330 1380 1480

Bhp 1.75 2.46 2.60 3.01 3.40 3.52 4.00 4.30 4.50 4.80 5.30 5.66

8,000Rpm 980 1033 1080 1150 1170 1250 1290 1310 1365 1410 1460 1522

Bhp 3.30 3.50 3.65 4.13 4.35 5.00 5.20 5.35 5.90 6.30 6.64 7.20

9,000Rpm 1105 1120 1200 1240 1300 1330 1385 1430 1460 1510 1590 1620

Bhp 4.80 4.90 5.20 5.40 6.20 6.40 7.00 7.20 7.50 8.30 9.26 10.40

10,000Rpm 1230 1250 1320 1326 1390 1415 1460 1515 1530 1580 1625

Bhp 6.00 6.80 7.03 6.80 7.80 8.20 8.46 9.45 9.70 10.50 10.90


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Compressor Rotation To determine whether or notcompressor is rotating in the proper direction:

1. Connect service gages to suction and discharge pressurefittings.

2. Energize the compressor.

3. The suction pressure should drop and the discharge pres-sure should rise, as is normal on any start-up.

4. If the suction pressure does not drop and the dischargepressure does not rise to normal levels.

5. Note that the evaporator fan is probably also rotating in

the wrong direction.

6. Turn off power to the unit and tag disconnect.

7. Reverse any two of the unit power leads.

8. Reapply power to the unit.

9. The suction and discharge pressure levels should nowmove to their normal start-up levels.

NOTE: When the compressor is rotating in the wrong direc-tion, the unit makes an elevated level of noise and does notprovide cooling.

Operating Sequence All units require the additionof a thermostat accessory package to complete the control cir-cuit. The sequence of operation may vary depending on whichpackage is selected.

ROOM-MOUNTED THERMOSTAT These units use anelectronic, communicating electronic, or mechanical thermo-stat mounted in the conditioned space.

FAN CIRCULATION When the fan selector switch is setto the ON position, the indoor-fan motor is energized throughG on the thermostat and the indoor-fan contactor is energized.This starts the indoor fan motor (IFM). The fan will operate toprovide continuous air circulation.

COOLING The indoor fan will operate continuously orwhen the compressor runs, depending on the setting of the ther-mostat fan selector switch. When the thermostat closes (on acall for cooling Y1 on the thermostat), the control relay (CR),outdoor-fan contactor (OFC) and compressor contactor(s) (C1and C2 on 20 ton) close. The control relay will start the indoor

fan if it is not already running. The outdoor-fan contactor willstart the condenser fan and the compressor contactors will im-mediately start the first stage compressor(s). The 50BYN024unit as wired from the factory has two compressors on firststage and one on second stage. This may be altered (see appli-cation data section of the product data catalog).

A second stage on 50BYN012-024 units will close if addi-tional cooling demand is required, and will then start thesecond-stage compressor. When the thermostat is satisfied, thesecond stage compressor will stop first, and then the first stagecompressors will stop when cooling demand is satisfied. Theoutdoor fan will also stop as soon as the first stage cooling issatisfied.

HEATING The indoor fan will operate continuously orwhen the heater runs, depending on the setting of the thermo-

stat fan selector switch. When the thermostat closes (on a callfor heating), the thermostat activates the water or steam controlvalve or electric heater to meet heating requirements.

CARRIER TEMP THERMOSTAT The Carrier TEMPSystem is a control system which includes a relay pack, TEMPsystem thermostat, sensors and appropriate wiring. The TEMPthermostat is the system controller and works much like a roomthermostat, but provides for communicating control. TheTEMP thermostat requires the addition of an accessoryrelay pack to interface with the unit. This relay pack may be

mounted in the low-voltage control compartment. The systemoperation is the same as stated in the Room-Mounted Thermo-stat section above.

CARRIER VARIABLE VOLUME AND TEMPERATURE(VVT) SYSTEM The VVT system is a control systemthat includes a relay pack (which may be mounted in the lowvoltage control compartment); monitor thermostat; zone controllers modulating supply duct dampers; modulating bypasscontroller sensors; and appropriate wiring. The VVT thermo-stat is the system controller. It sends messages to the relay packwhich then sends the appropriate signals to the 50BYN unit for

fan, heating and cooling. The monitor thermostat also gathersinformation from the zone controllers, which control the zonesupply dampers. It provides a zoned, all-air system for bothheating and cooling which supplies variable volume, variabletemperature air to the zones conditioned.

ALL UNITS The control circuit incorporates a currentsensing lockout relay (Cycle-LOC device) that locks off thecompressor(s) when any safety device is activated (low or highpressure switches, outdoor-fan motor overload, or compressointernal overload). If any compressor safety device opens, thecompressor(s) will stop and a 24-v signal will be sent to the Xconnection of the low-voltage terminal strip. The signal may beused to light an indicator light on the thermostat to show thaservice is required on the unit. Since the unit is protected by theCycle-LOC device, the compressor(s) will not restart following

a safety interruption unless the thermostat is satisfied withoucooling operation. To reset the Cycle-LOC control devicemanually turn the control power to the OFF, then back to theON position. High- and low-pressure switches and motor overload protectors will reset automatically when the conditionwhich caused the device to trip has dropped below the resetcondition. A 5-minute timer (Time-Delay Relay [TDR]) wilprevent the compressor(s) from restarting for 5 minutes afterany compressor has stopped.

If the condenser-fan motor overheats due to motor over-loador lack of cooling air, the internal fan protector will open thecircuit internally in the motor, and the fan will stop. If a safetycontrol in the unit opens, the condenser fan will also stop.

ACCESSORIES Low ambient control on 50BYN units isaccomplished with a refrigerant operated damper located onthe condenser fan discharge. Low ambient operation does notaffect operating sequence.

WINTERSTART Since these units are equipped with a27 psig low-pressure switch, a 3-minute low-pressure switchbypass is recommended for operation below 50 F. Order Winter Start Control accessory no. CRWINSTR01A00 and instalaccording to the instructions supplied with the kit.

DEFROST THERMOSTAT (50BB-900- - -001) This thermostat is installed on the evaporator coil and is recommendedwith Winter Start control. Install thermostat according to instructions supplied with the kit.

ECONOMIZER When the thermostat turns the indoor fanon, the economizer relay is energized and the actuator ipowered on. The actuator moves the dampers to the minimum

position as determined by the adjustment potentiometer onthe actuator. If the system uses a CO2 sensor, the minimumposition is determined by the potentiometer on the requiredfield-supplied adapter. On a call for heating from the thermostat (W1 and/or W2 energized), the economizer remains at theminimum position.

NOTE: If a CO2 sensor is used, the economizer can modu-late based on the carbon dioxide level in the space. There isno low leaving-air temperature limit control. Controls toaccomplish this must be field-supplied and installed.

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On a call for cooling from the thermostat (Y1 energized),the actuator logic module determines if the outdoor air en-thalpy is acceptable according to the set point on the actuator. Ifthe outdoor air enthalpy is acceptable, the economizer begins tomodulate open and is controlled to maintain a 56 F leaving airtemperature. If outdoor air enthalpy is unacceptable, the logicmodule bypasses the use of outdoor air and energizes Y1 of theunit. On a call for a second stage of cooling (Y2 energized), theactuator energizes Y1 on the unit if the outdoor air enthalpy isacceptable. If the outdoor air is unacceptable, the actuator logicmodule energizes Y2 of the unit. When the system is equipped

with a CO2 sensor in a modulating configuration, the followingapplies: If the system is operating in the Cooling mode and thedemand for fresh air to reduce the carbon dioxide level in thespace is greater than the cooling load demand, the actuatormodulates to reduce the carbon dioxide level and does notmodulate towards closed if the leaving-air temperature isbelow 56 F. If, however, the cooling demand is greater than thedemand to reduce the carbon dioxide level, the actuator modu-lates open and controls to a 56 F leaving-air temperature.

The damper modulates open when the leaving-air tempera-ture demand is greater than the airflow demand required for theCO2 sensor to reduce carbon dioxide levels. When the CO2sensor is installed, there is no minimum leaving air temperaturecontrol at the economizer.

USING A CO2 SENSOR WITH THE ECONOMIZER

A separately ordered carbon dioxide sensor can be used to sig-nal the economizer to open the outdoor-air dampers to admitfresh air and dilute the indoor CO2 level. Sensor descriptionsand part numbers are shown below.

The CO2 sensors listed above are all factory set for a rangeof 0 to 2000 ppm and a linear voltage output of 2 to 10 vdc.The relay normally open dry contacts (TB-3 and TB-4) are fac-tory set to close at 1000 ppm. Refer to the installation instruc-tions with the CO2 sensor for electrical ratings of contacts andinformation on connecting to power supply. Switch contactscan be used to set off an alarm or light to indicate CO 2 levelshigher than the switch set point. Any changes to the factoryconfiguration require the purchase of the User InterfaceProgram (UIP) or Sensor Calibration Service Kit, which alsocontains the UIP. For correct modulation of the economizeractuator motor, a separately ordered adapter (Honeywellpart no. Q769C1007) is required.

SERVICE

Cleaning Evaporator and Condenser Coils Donot use high-pressure water or air. Damage to fins may result.Clean coils with a vacuum cleaner, fresh water, compressed air,or a bristle brush (not wire). Backflush coil to remove debris.Commercial coil cleaners may also be used to help removegrease and dirt. Steam cleaning is NOT recommended.

Units installed in corrosive environments should be cleanedas part of a planned maintenance schedule. In this type of appli-cation, all accumulations of dirt should be cleaned off the coil.

Take care not to get water in the system ducts or unitinsulation.

Lubrication Fan motors have permanently lubricatedbearings.

Condenser Fan Adjustment To prevent personalinjury, be sure wire fan guards are secured in place over eachfan discharge (or that fans are ducted) before starting the unit.

TO CHANGE FAN SPEED

1. Shut off unit power supply.

2. Loosen fan belt by loosening fan motor from mountingbracket. Do not loosen fan motor mounting bracket fromunit.

3. Loosen movable pulley flange setscrew (Fig. 15).

4. Screw movable flange toward fixed flange to increase fanspeed and away from fixed flange to decrease speed. In-creasing fan speed increases load on motor. Do not ex-ceed maximum allowable fan speed or motor full loadamps indicated on motor nameplate and in Table 2.

5. Set movable flange setscrew at nearest flat of pulley huband tighten setscrew.

6. Check pulley alignment and belt tension adjustment asdescribed below.

7. Check fan operation. Repeat above procedure as required.

Pulley Alignment Shut off unit power supply. Loosenfan motor pulley setscrews and slide fan pulley along fan shaft.Make angular alignment by loosening motor from mountingbracket (see Fig. 15). Check alignment with a straightedge.

Belt Tension Adjustment Shut off unit power sup-ply. Loosen fan motor mounting plate bolts. Do not loosenmotor mounting bracket from unit. Move fan motor mountingplate until proper belt tension is achieved (approximately 1/2-in.deflection with 8-lb tension at midpoint of belt span).

Changing Fan Wheel If a fan wheel should fail, itmay be replaced as follows:

1. Remove belts from fan pulley.

2. Loosen locking collars on the fan bearings and set screwson the fan wheels.

3. Remove the shaft through the access panel on either sideof the unit.

4. Remove the fan cut-off plate in the fan discharge.

5. Remove the fan wheel through the fan discharge opening.

6. Replace the wheel, and reverse Steps 1-4 above.

Fan Bearing Replacement If a fan bearing fails,replace it as follows:

1. Remove belts from the fan pulley.

2. Support fan shaft.

3. Loosen locking collar on fan bearing.

4. Remove bearing from the shaft.

5. Install new bearing onto the shaft, and reverse Steps 1-3above.

Concentric Alignment Shaft and wheels must beconcentrically centered with the venturi or air inlet of the fanhousing (see Fig. 16).

Shaft bearings are supports by bearing supports (Fig. 17). Ifshaft and wheels are concentrically misaligned from shippingshock, it is possible to rebend the bearing support arms to theoriginal positions. Replace the bearing support if it has exten-sive damage.

CO2 SENSOR ACCESSORIES

Part Numbers Description

CGCDXSEN001A00Wall Mount Sensor(No Display)

CGCDXSEN002A00Wall Mount SensorWith Display

CGCDXSEN003A00Duct Mount Sensor(No Display)

CGCDXGAS001A00Sensor CalibrationService Kit

CGCDXPRM001A00

User Interface Program

(UIP)

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MAINTENANCE

Cleaning The unit should be thoroughly cleaned insideand out. Frequency of cleaning will depend on unit locationand area conditions. Drains must be kept free of dirt and trashCoils can be cleaned with a stiff brush, vacuum cleaner, orcompressed air. Coil can be reached through access panels.

Inspection Check coil baffles for tight fit to prevent airfrom bypassing the coil. Check panels for air leakage, particu-larly those sealing the fan and coil compartments. Check foloose electrical connections, oil level, proper refrigeran

charge, and refrigerant piping leaks. The fan motor and fanshaft bearings are permanently lubricated. Further lubricationis not required. Before start-up, be sure all service valves areopen (backseated).

Air Filters Air filters may be installed on the condenserair inlet. Air filters should be replaced or cleaned on a regularbasis depending on how dirty the operating environment isFailure to clean air filters regularly will result in loss of uniperformance and possible nuisance tripping of the high-pressure switch.

Condensate Drain If the unit is used with a conden-sate drain to remove rain water, the drain pan and trap shouldbe cleaned at least twice per year. After cleaning, test the con-densate drain for proper operation by pouring a bucket of wate

into the condensate drain pan. The water should flow out immediately and evenly.

Checking System Charge

NOTE: Condenser airflow must be properly set beforechecking system charge.

50BYN units are shipped with full operating charge. If re-charging is necessary:

1. Insert thermometer bulb in insulating rubber sleeve onliquid line near filter drier. Use a digital thermometer forall temperature measurements. DO NOT use a mercuryor dial-type thermometer.

2. Connect pressure gage to discharge line near compressor

3. After unit condition have stabilized, read head pressure

on discharge line gage.NOTE: Operate unit a minimum of 15 minutes beforechecking charge.

4. From standard Pressure-Temperature charge for R-22find equivalent saturated condensing temperature.

5. Read liquid line temperature on thermometer; then subtract from saturated condensing temperature. The differ-ence equals subcooling temperature.

6. Compare the subcooling temperature with the normatemperature listed in Table 5. If the measured liquid linetemperature does not agree with the required liquid linetemperature, ADD refrigerant to raise the temperature orREMOVE refrigerant (using standard practices) to lowerthe temperature (allow a tolerance of 3 F).

Example:Head pressure (from gage). . . . . . . . . . . . . . . 220 psigSaturated condensing temp (from chart) . . . . . . .108 FLiquid line temp (from thermometer) . . . . . . . . . .96 FSubcooling (by subtraction). . . . . . . . . . . . . . . . . .12 F(add charge)

Fig. 15 Fan Pulley Adjustments

Fig. 16 Concentric Alignment

Fig. 17 Fan Shaft Bearings

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Table 5 Subcooling Temperature

*Saturated condensing temperature at compressor minus liquid linetemperature.

NOTE: Do not vent or depressurize unit refrigerant to atmo-sphere. Remove and reclaim refrigerant following acceptedpractices.

Access Panel Removal

TOP PANEL Remove 2 screws, pull out bottom of panel,and lift up to remove.

CONTROL PANEL Remove 2 screws and lift up to re-move the panel.

BOTTOM PANEL Remove control panel. Then remove2 screws in bottom panel and lift up to remove the panel.

Evaporator-Fan Motor Removal

Motor power wires need to be disconnected from motor ter-minals before motor is removed from unit.

1. Shut off unit main power supply.

2. Loosen bolts on mounting bracket so that fan belt can beremoved.

3. Loosen and remove the 2 motor mounting bracket boltson left side of bracket.

4. Slide motor/bracket assembly to extreme right and lift outthrough space between fan scroll and side frame. Restmotor on a high platform such as a step ladder. Do not al-low motor to hang by its power wires.

Pressure Relief Device All units are equipped witha fusible-plug type safety relief device on the refrigerant tub-

ing. The relief setting is 197 F or 203 F on all units.

Cycle-LOC Protection Device All units areequipped with Cycle-LOC current-sensing lockout relay oneach circuit. This device will lock out the compressor after anysafety trip (high-pressure switch, low-pressure switch, or inter-nal overload of the compressor). Check reason for lockout be-fore resetting the device. Refer to unit label wiring diagram onthe unit. To reset, turn the thermostat system switch to OFF,then back to COOL position.

Time Guard II Control Each circuit (all units) isequipped with Time Guard II control, which provides a5-minute time delay after unit is deenergized. This preventsrapid cycling of the unit caused by thermostat movement or abrief power interruption and reverse rotation of the compressor

scroll (single-phase units only) after a brief power interruption.

High and Low Pressurestats The high pressur-estat is located on the compressor discharge line. The low pres-surestat is located on the suction line.

Oil Charge All units are factory charged with oil (seeTable 1). It is not necessary to add oil unless the compressor isremoved from the unit. If additional oil is needed, do not usemineral oils. Only synthetic oils are satisfactory.

UNIT 50BR,BZ SUBCOOLING*

006-016 20 2 F

To prevent personal injury, wear safety glasses and gloveswhen handling refrigerant. Do not overcharge system

this can cause compressor flooding.

Before attempting to remove fan motors or motor mounts,place a piece of plywood over evaporator coils to preventcoil damage.

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TROUBLESHOOTING

Refer to Table 6 to determine the possible cause of the problem and the associatedprocedure necessary to correct it. See Fig. 18 for typical wiring.

Table 6 Troubleshooting Procedure

LEGEND

PROBLEM POSSIBLE CAUSE CORRECTION PROCEDURE

Unit will not start. Loss of unit power Check power source.Check fuses, circuit breakers, disconnect switch.Check electrical contacts.

Unit voltage not correct Check and correct.

Open fuse Check for short circuit in unit.Open protecti on dev ice Check relays , c ontac ts, pres sure swi tc hes.

Unit or motor contactor out of order Test and replace if necessary.

Fan does not operate. Contactor or relay overload or out of order Test and replace if necessary.

Motor defective Test and replace if necessary.

Broken belt Replace belt.

Loose electrical contact Tighten contact.

Compressor is noisy, butwill not start.

Under voltage Check and correct.

Defect in compresso r motor Replace compressor.

Missing phase Check and correct.

Compressor seized Check and replace if necessary.

Compressor starts, butdoes not continue to run.

Compres sor or c ontact defect Test and replace if nec es sary.

Unit is under charged Check and corre ct any leaks. Add refrigerant.

Unit is too big Check load calculation.

Compres sor is overloaded C heck prot ect ion dev ic e and replace.Check for missing phase.Check TXV.Check temperature in suction discharge line.

Unit is noisy. Compressor noise Check TXV and replace if necessary.Check internal noise.

Tube vibration or condenser water problem Check and correct.

Unit panel or part vi brati ng Check and tight en appropriate part.

Unit runs continuously,but has low capacity.

Unit is too small Check load calculation.

Low refrigerant or noncondensing gas present Check for leaks and add refrigerant or gas as necessary.

Dirty condenser coil Check and correct.

Compressor defect Check pressure and amps. Replace if necessar y.

Insufficient flow of refrigerant in evaporator Check filter drier and replace if necessary.Check TXV and adjust or replace if necessary.Check position of TXV bulb and equalizer.

Low airflow Check filters, and clean or replace as necessary.

Check coils, and clean as necessary.Check for restrictions in ductwork.Check fan rotation and adjust.Check fan motor.Check belts for wear.

Oil in evaporator Drain evaporator.

High discharge pressure. Low airflow in condenser Check fan rotation.Check motor, and replace if necessary.Check belts, and replace if necessary.Check coils, and clean if necessary.

Dirty condenser coil Clean condenser.

High temperature in condenser air or airrecirculation

Check for short circuit of air.Check water supply installation.

Overcharged Check and reclaim excess charge.Adjust subcooling.

Nonc ondensing gas present Ver ify and correct.

TX V Thermostatic Expansion Valve

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Table 6 Troubleshooting Procedure (cont)

LEGEND

PROBLEM POSSIBLE CAUSE CORRECTION PROCEDURE

Discharge pressure toolow

Outdoor tem perature too l ow Install low -ambient c ontrol.

Condenser airflow too high Check and adjust.

Low charge Check for and repair leaks and add refrigerant as necessary.

Compressor fault Check suction and discharge pressure.

Suction pressure too low Discharge pressure is low See Discharge Pressure Too Low section of this table above.

Low thermal load Check building load.

Low refrigerant Check for and repair leaks and add refrigerant as necessary.

Low airflow in evaporator Clean filter.

Remove scale.Check for blockage in ducts.Check fan rotation.Check motor operation.Check belts.

Low refrigerant flow in evaporator Check for obstruction in filter drier.Check for obstruction in TXV.Check super heating.Check position of TXV bulb and equalizer.

Suction pressure too high High thermal load Check design conditions.

Compressor defect Check pressures, and replace if necessary.

Condensate water leaks Defective connection Check and correct.

Blocked drain Clean drain pan.

Drain lines incorrect Check and correct.

TX V Thermostatic Expansion Valve

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LEGEND

C Compressor ContactorCB Circuit BreakerCLO Compressor LockoutCR Control RelayEQUIP Equipment

GND GroundHPS High-Pressure SwitchIFC Indoor-Fan ContactorIFM Indoor-Fan MotorIFP Indoor-Fan ProtectorLPS Low-Pressure SwitchNEC National Electrical CodeOFC Outdoor-Fan ContactorOFM Outdoor-Fan MotorOFP Outdoor-Fan Protector

TB Terminal BlockTDR Time-Delay RelayTRAN Transformer

Terminal Block Connection

Marked Terminal

Unmarked Terminal

Splice

Factory Wiring

Field Control Wiring

Fig. 18 Typical Wiring Schematic, 50BYN Units

NOTES:1. Fan motors are inherently thermally protected.2. Three-phase motors are protected under primary

single phase conditions.3. Use conductors suitable for at least 194 F (90 C)

when replacing factory wiring.4. Use copper conductors only.5. Wiring for field power supply must be rated at 165 F

(75 C) minimum.

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Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

PC 111 Catalog No. 535-00136 Printed in U.S.A. For m 50BYN-1SI Pg 26 2-04 Replaces: 50BY-1SIBook 1 4

Tab 2 b 7 a

Copyright 2004 Carrier Corporation

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START-UP CHECKLIST

(Fill out this form on Start-Up and file in job folder)

I. PRELIMINARY INFORMATION

50BYN UNIT: MODEL NO. ____________________ SERIAL NO. ____________________

FIELD-INSTALLED ACCESSORIES: _____________________________________________________________________

START-UP DATE: ______________________________________

II. PRE-START-UP:

VERIFY ALL SHIPPING MATERIALS HAVE BEEN REMOVED FROM THE UNIT

IS THERE ANY SHIPPING DAMAGE? ________________ IF SO, WHERE ________________

_________________________________________________________

WILL THIS DAMAGE PREVENT UNIT START-UP? (Y/N) _______

CHECK POWER SUPPLY. DOES IT AGREE WITH UNIT? (Y/N) _______

HAS THE GROUND WIRE BEEN CONNECTED? (Y/N) _______

HAS THE CIRCUIT PROTECTION BEEN SIZED AND INSTALLED PROPERLY? (Y/N) _______

ARE THE POWER WIRES TO THE UNIT SIZED AND INSTALLED PROPERLY? (Y/N) _______HAVE CONDENSER AND EVAPORATOR FAN AND MOTOR PULLEYS BEEN CHECKED FOR PROPERALIGNMENT AND DO THE FAN BELTS HAVE PROPER TENSION? (Y/N) _______

HAS CORRECT FAN ROTATION OR EVAPORATOR AND CONDENSER BEEN CONFIRMED? (Y/N) _______

VERIFY CONDENSATE DRAIN AND RAIN DRAIN HAVE BEEN INSTALLED PER INSTRUCTIONS

HAS WATER BEEN PLACED IN DRAIN PAN TO CONFIRM PROPER DRAINAGE? (Y/N) _______

ARE PROPER AIR FILTERS IN PLACE AND ARE FILTERS CLEAN? (Y/N) _______

VERIFY UNIT IS INSTALLED WITHIN LEVELING TOLERANCES

CONTROLS

HAVE THERMOSTAT CONNECTIONS BEEN MADE AND CHECKED? (Y/N) _______ARE ALL WIRING THERMINALS (including main power supply) TIGHT? (Y/N) _______

IF LOW AMBIENT HEAD PRESSURE CONTROL DAMPER IS USED HAS IT BEEN CONNECTED ANDCHECKED

PIPING

HAVE LEAK CHECKS BEEN MADE AT COMPRESSOR, CONDENSER, EVAPORATOR,TXVs (Thermostatic Expansion Valves), SOLENOID VALVES, FILTER DRIERS, AND FUSIBLE PLUGS WITH ALEAK DETECTOR? (Y/N) _______

LOCATE, REPAIR, AND REPORT ANY LEAKS

HAVE SERVICE VALVES FOR SPLITTING UNIT ON 20 TON UNIT OPENED? (Y/N) _______

CHECK VOLTAGE IMBALANCE

LINE-TO-LINE VOLTS: AB V AC V BC V

(AB + AC + BC)/3 = AVERAGE VOLTAGE = V

MAXIMUM DEVIATION FROM AVERAGE VOLTAGE = V

VOLTAGE IMBALANCE = 100 X (MAX DEVIATION)/(AVERAGE VOLTAGE) = %

IF OVER 2% VOLTAGE IMBALANCE, DO NOT ATTEMPT TO START SYSTEM!

CALL LOCAL POWER COMPANY FOR ASSISTANCE.

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-------------------------------------------------------------------------------------------------------

-------------------------------------

-------------------------------------

CUTALONGDOTTEDLINE

CUTALON

GDOTTEDLINE

III. START-UP

CHECK INDOOR (EVAPORATOR) FAN SPEED AND RECORD.

CHECK INDOOR (CONDENSER) FAN SPEED AND RECORD.

AFTER AT LEAST 15 MINUTES RUNNING TIME, RECORD THE FOLLOWING MEASUREMENTS:

COMPRESSOR AMPS:

NOTES: _______________________________________________________________________________________

_______________________________________________________________________________________________

_______________________________________________________________________________________________

_______________________________________________________________________________________________

CIRCUIT 1CIRCUIT 2

(If Applicable)CIRCUIT 3

(If Applicable)

SUCTION PRESSURE

SUCTION LINE TEMPDISCHARGE PRESSURE

DISCHARGE LINE TEMP

SATURATED SUCTION TEMP

SATURATED CONDENSING

SUPERHEAT DEGREES

SUBCOOLING DEGREES

ENTERING CONDENSER-AIR TEMP

LEAVING CONDENSER-AIR TEMP

EVAP ENTERING-AIR DB (dry bulb) TEMP

EVAP ENTERING-AIR WB (wet bulb) TEMP

EVAP LEAVING-AIR DB TEMPEVAP LEAVING-AIR WB TEMP

L1

L2

CONDENSER FAN AMPS:

SUPPLY FAN AMPS:

50byn

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