Bryant Durapac Plus 551a User Manual

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installation, start-up and service instructions

SINGLE PACKAGE ROOFTOP ELECTRIC COOLING/ELECTRIC HEATING UNITS

Cancels: II 551A-155-2 II 551A-155-3

Dura

Plus Series

Pac

Sizes 155-240

551A

3/1/01

CONTENTS

Page

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

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-17

I. Step 1 — Provide Unit Support. . . . . . . . . . . . . . . . . 1

II. Step 2 — Rig and Place Unit. . . . . . . . . . . . . . . . . . . 1

III. Step 3 — Field Fabricate Ductwork . . . . . . . . . . . . . 7

IV. Step 4 — Make Unit Duct Connections . . . . . . . . . . .7

V. Step 5 — Trap Condensate Drain . . . . . . . . . . . . . . . 7

VI. Step 6 — Make Electrical Connections

VII. Step 7 — Make Outdoor-Air Inlet

Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

VIII. Step 8 — Install Outdoor-Air Hood. . . . . . . . . . . . . 12

IX. Step 9 — Install All Accessories . . . . . . . . . . . . . . 15

X. Step 10 — Install Humidistat for Optional

Perfect Humidity™ Dehumidification Package . . 16

START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18-25

SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26-32

TROUBLESHOOTING. . . . . . . . . . . . . . . . . . . . . . . . . . . .33,34

START-UP CHECKLIST . . . . . . . . . . . . . . . . . . . . . . . . . . CL-1

SAFETY CONSIDERATIONS

Installation and servicing of air-conditioning equipment can be hazardous due to system pressure and electrical components. Only trained and qualified service personnel should install, rep air, or service air-conditioning equipment.

Untrained personnel can perform basic maintenance functions of cleaning coils and filters and replacing filters. All other operations sh o uld be perfor me d by trai ne d se rvi ce personnel. When working on air-conditioning equipment, observe precautions in the literature, tags and labels attached to the unit, and other safety precaution s that may apply.

Follow all safety codes. Wear safety glasse s and work g love s. Use quenching cloth for unbrazing operations. Have fire extinguishers available for all brazing operations.

WARNING:

Before performing service or mainte-

. . . . . . . . . . . . 8

nance operations on unit, turn off main power switch to unit. Electrical shock could cause personal injury.

IMPORTANT: Units have high ambient operating limits. If limits are exceeded, the unit will automatically lock the compressor out of operation. Manual reset will be required to restart the compressor.

INSTALLATION

I. STEP 1 — PROVIDE UNIT SUPPORT

A. Roof Curb

Assemble and install accessory roof curb or horizontal supply roof curb in accordan ce with instructions shipped with the accessory. Accessory roof curb and horizontal supply roof curb and information required to field fabricate a roof curb or horizontal supply roof curb are shown in Fig. 1 and 2. Install insulation, cant strips, roofing, and counter flashing as shown. Ductwork can be secured to roof curb before unit is set in place.

IMPORTANT: The gasketing of the unit to the roof curb or horizontal supply roof curb is critical for a leakproof seal. Install gasket supplied with the ro of curb or h orizontal supply roof curb as shown in Fig. 1. Improperly applied gasket can result in air leaks and poor unit performance.

Roof curb must be level. This is necessary to permit unit drain to function properly. Unit leveling tolerance is ± per linear ft in any direction. Refer to Accessory Roof Curb or Horizontal Supply Roof Curb Installation Instructions for additional information as required.

B. Alternate Unit Support

When the curb or adapter cannot be used, support unit with sleepers using unit curb or adapter s upport area. If sl eepers cannot be used, su ppor t l on g si des o f unit with a minimum of 3 equally spaced 4-in. x 4-in. pads on each side.

II. STEP 2 — RIG AND PLACE UNIT

Inspect unit for transportation da mage. File any claim with transportation agency. Keep unit upright, and do not drop. Use spreader bars over unit to prevent sling or cable damage. Rollers may be used to move unit across a roof. Level by using unit frame as a reference; leveling tolerance is

/16 in. per linear ft in any direction. See Fig. 3 for addi-

tional information. Unit weight is shown in Table 1. Four lifting holes are provided in ends of unit base rails as

shown in Fig. 3. Refer to rigging instructions on unit.

A. Positioning

Provide clearance around and above unit for airflow, safety, and service access (Fig. 4 and 5).

Do not install unit in an indoor location. Do not locate air inlets near exhaust vents or other sources of contaminated air.

Although unit is weatherproof, guard against water from higher level runoff and overhangs.

B. Roof Mount

Check building codes for weight distribution requirements.

/16 in.

NOTES:

1. Roof curb accessory is shipped disassembled.

lb density.

.28 .45 .28 .43

DIMENSIONS* (DEGREES AND INCHES)

UNIT

Deg. in. Deg. in.

ALL

thick neoprene coated 1

″

90 degree elbow must be installed on the supply ductwork

To prevent the hazard of stagnant water build-up in the drain pan of

2. Insulated panels: 1

3. Dimensions in ( ) are in millimeters.

below the unit discharge for units equipped with electric heaters.

4. Direction of airflow.

5. Roof curb: 16 ga. (VA03-56) stl.

NOTE:

the indoor section, unit can only be pitched as shown.

DESCRIPTION

CURB

HEIGHT

Fig. 1 — Roof Curb Details

High

″

Standard Curb

for Units Requiring

Standard Curb

″

-2

′

High Installation

″

-0

′

(610)

(305)

High-Static

Side Supply and

Transition Duct

Return Curb for

High Installation

″

-0

′

(610)

PKG. NO. REF.

CRRFCURB011A00

CRRFCURB010A00

CRRFCURB013A00

CRRFCURB012A00

—2—

NOTE:

For preassembled horizontal adapter roof curb part no. CRRFCURB013A00, the accessory kit includes a factory-designed, high-static, regain transition duct. For horizontal curb part no. CRRFCURB012A00, a field-supplied transition duct is required.

Fig. 2 — Horizontal Supply Roof Curb and Horizontal

Adapter Roof Curb

UNIT 551A

155 180 240

NOTES:

1. Dimensions in ( ) are in millimeters.

2. Refer to Fig. 4 and 5 for unit operating weights.

3. Remove boards at ends of unit and runners prior to rigging.

4. Rig by inserting hooks into unit base rails as shown. Use corner post from packaging to protect coil from damage. Use bumper boards for spreader bars.

5. Weights do not include optional EconoMi$er. Add 80 lb (36 kg) for EconoMi$er weight.

6. Weights given are for aluminum evaporator and condenser coil plate fins. Weights include electric heat.

7. Add 75 lb (34 kg) for crating on 551A155 and 180 units. Add 135 lb (61 kg) for crating on 551A240 units.

8. Add 150 lb (68 kg) for copper condenser coil. Add 280 lb (127 kg) for copper condenser and evaporator coils.

MAXIMUM

SHIPPING WEIGHT

lb kg ft-in. mm ft-in. mm

1625 737 6-11 1700 771 6-11 1800 816 6-11

DIMENSIONS

/22121 4- 0 1219

/22121 3-10 1168

/22121 3- 7 1092

CAUTION:

All panels must be in place when rigging.

Fig. 3 — Rigging Details

—3—

(8) on each

″

′

DIM A DIM B DIM C

CORNER

(2134) for coil removal. This dimension can be reduced to

CORNER

1. Refer to print for roof curb accessory dimensions.

2. Dimensions in ( ) are in millimeters.

3. Center of Gravity.

NOTES:

4. Direction of airflow.

″

-0

′

(1219) if conditions permit coil removal from the top.

″

-0

′

• Rear: 7

5. Ductwork to be attached to accessory roof curb only.

6. Minimum clearance:

(1219) for proper condenser coil airflow.

″

-0

′

• Left side: 4

(1219) for proper operation of damper and power

″

-0

′

(1219) for control box access.

″

-0

′

• Front: 4

• Right side: 4

(1829) to assure proper condenser fan operation.

″

-0

′

exhaust if so equipped.

• Top: 6

• Local codes or jurisdiction may prevail.

damper/ power exhaust as stated in Note #6, a removable fence or

7. With the exception of clearance for the condenser coil and the

90 degree elbow must be installed on the supply ductwork A

below the unit discharge for units equipped with electric heaters.

side for top cover drip edge.

barricade requires no clearance.

9. See drawing 50TJ500352 for service option details.

8. Dimensions are from outside of corner post. Allow 0

10.

CORNER

ECONOMI$ER

STD UNIT

WEIGHT

UNIT

551A

Lb Kg Lb Kg Lb Kg Lb Kg Lb Kg Lb Kg ft-in. mm ft-in. mm ft-in. mm

1575 714 80 36.3 407 185 375 170 383 174 410 186 3-5 1039 3-5 1054 1-10 559

1650 748 80 36.3 375 170 375 170 449 204 452 205 3-2 963 3-7 1092 1-10 559

155

180

Fig. 4 — Base Unit Dimensions, 551A155 and 180

—4—

(8) on

″

′

DIM A DIM B DIM C

CORNER

ECONOMI$ER

STD UNIT

UNIT

WEIGHT

Lb Kg Lb Kg Lb Kg Lb Kg Lb Kg Lb Kg ft-in. mm ft-in. mm ft-in. mm

551A

1750 794 80 36.3 420 191 395 179 448 203 486 221 3-3 988 3-5 1054 1-8 508

240

(1219) if conditions permit coil removal from the

″

-0

(2134) for coil removal. This dimension can be

′

″

-0

′

reduced to 4

top.

1. Refer to print for roof curb accessory dimensions.

2. Dimensions in ( ) are in millimeters.

3. Center of Gravity.

NOTES:

4. Direction of airflow.

5. Ductwork to be attached to accessory roof curb only.

6. Minimum clearance:

• Rear: 7

(1219) for proper condenser coil airflow.

″

(1219) for control box access.

-0

′

″

-0

′

• Front: 4

• Left side: 4

(1219) for proper operation of damper and power

″

-0

′

(1829) to assure proper condenser fan operation.

″

-0

′

exhaust if so equipped.

• Right side: 4

• Top: 6

• Local codes or jurisdiction may prevail.

7. With the exception of clearance for the condenser coil and the

damper/ power exhaust as stated in Note #6, a removable fence

or barricade requires no clearance.

8. Dimensions are from outside of corner post. Allow 0

90 degree elbow must be installed on the supply ductwork

each side for top cover drip edge.

below the unit discharge for units equipped with electric

heaters.

9. See drawing 50TJ500352 for service option details.

10.

Fig. 5 — Base Unit Dimensions, 551A240

—5—

Table 1 — Physical Data

UNIT 551A NOMINAL CAPACITY (tons) OPERATING WEIGHT (lb)

Unit

Al/Al* Al/Cu*

Cu/Cu* EconoMi$er Roof Curb† Perfect Humidity™ Dehumidification Package

COMPRESSOR

Quantity...Model (Ckt 1, Ckt 2) Number of Refrigerant Circuits Crankcase Heater Watts Loading (% of Full Capacity) Oil (oz) (Ckt 1, Ckt 2)

REFRIGERANT TYPE

Expansion Device Operating Charge (lb)**

Circuit 1

Circuit 2

CONDENSER COIL

Rows...Fins/in. Total Face Area (sq ft)

CONDENSER FAN

Nominal Cfm Quantity...Diameter (in.) Motor Hp...Rpm Watts Input (Total)

EVAPORATOR COIL

Rows...Fins/in. Total Face Area (sq ft)

EVAPORATOR FAN

Quantity...Size (in.) Type Drive Nominal Cfm Std Motor Hp Opt Motor Hp

Motor Nominal Rpm Std Maximum Continuous Bhp Opt Maximum Continuous Bhp

Motor Frame Size Fan Rpm Range Low-Medium Static

Motor Bearing Type Maximum Allowable Rpm Motor Pulley Pitch Dia. Low-Medium Static

Nominal Motor Shaft Diameter (in.) Fan Pulley Pitch Diameter (in.) Low-Medium Static

Nominal Fan Shaft Diameter (in.) Belt, Quantity...Type...Length (in.) Low-Medium Static

Pulley Center Line Distance (in.) Speed Change per Full Turn of Movable Low-Medium Static Pulley Flange (Rpm) High Static Movable Pulley Maximum Full Turns

From Closed Position Factory Speed Factory Speed Setting (Rpm) Low-Medium Static

HIGH-PRESSURE SWITCH (psig)

Cutout Reset (Auto.)

LOW-PRESSURE SWITCH (psig)

Cutout Reset (Auto.)

FREEZE PROTECTION THERMOSTAT (F)

Opens Closes

High Static

OUTDOOR-AIR INLET SCREENS

Quantity...Size (in.)

RETURN-AIR FILTERS

Quantity...Size (in.)

LEGEND

Al — Bhp — Cu — TXV —

Aluminum Brake Horsepower Copper Thermostatic Expansion Valve

*Evaporator coil fin material/condenser coil fin material.

†Weight of 14-in. roof curb.

155 180 240

12 15 20

1575 1650 1750 1725 1800 1900 1855 1930 2030

80 80 80

200 200 200

40 40 40

1...ZR72KC, 1...ZR57KC 1...ZR94KC, 1...ZR72KC 1...ZR125KC, 1...ZR108KC 22 2

70 70 70

0, 56, 100 0, 60, 100 0, 60, 100

60, 66 85, 60 110, 110

20.7 19.5 18.5

11.9 13.45 13.3

Cross-Hatched

4...15 4...15 4...15

21.7 21.7 21.7

10,500 10,500 14,200

3...22 3...22 2...30

/2...1050

1100 1100 3400

Cross-Hatched

4...15 4...15 4...15

17.5 17.5 17.5

2...10 x 10 2...12 x 12 2...12 x 12 Belt Belt Belt

5200 6000 8000

2.9 5 7.5

3.7

1725 1745 1745

3.13 6.13 9.47 [208 v], 10.33 [230 v and 460 v]

4.38 N/A N/A 56H 184T 213T

834-1064 873-1021 1002 -1151

1161-1426 1025-1200 1193-1369

Ball Ball Ball

1,550 1,550 1,550

3.1/4.1 4.9/5.9 5.4/6.6

3.7/4.7 4.9/5.9 5.4/6.6

6.0 9.4 9.4

5.2 8.0 7.9

1...BX...42 1...BX...50 1...BX...54

1...BX...42 1...BX...48 1...BX...50

13.5-15.5 13.3-14.8 14.6-15.4 58 37 37 67 44 44

4†† 4†† 4††

3.5 3.5 3.5

978 965 1095

1327 1134 1303

/8-in. Copper Tubes, Aluminum Lanced, Aluminum Pre-Coated,

/8-in. Copper Tubes, Aluminum Lanced or Copper Plate Fins, Face Split

**Circuit 1 uses the lower por tion of condenser coil and lower por tion of evapora-

tor coils, and Circuit 2 uses the upper portion of both coils.

††Due to belt and pulley style, pulley cannot be set from 0 to 1

R-22

TXV

or Copper Plate Fins

Propeller Type

/2...1050 1...1075

Centrifugal Type

11/

17/

426 320

27 44

30 ± 5 45 ± 5

Cleanable

2...20 x 25 x 1

1...20 x 20 x 1 Throwaway

4...20 x 20 x 2

4...16 x 20 x 2

13/

17/

/2 turns open.

—6—

III. STEP 3 — FIELD FABRICATE DUCTWORK

3/4" FPT DRAIN CONNECTION

1-3/8" DRAIN HOLE

INDOOR FAN MOTOR ACCESS

FILTER ACCESS

Secure all duct s to bu ilding struct ure. Use fl exible duct con nectors between unit and ducts as required. Insulate and weatherproof all external ductwork, joints, and roof openings with counter flashing and m asti c i n acc ordance with applicable codes.

Ducts passing through a n unc ondit i one d spa ce must be insulated and covered with a vapor barrier.

The 551A units with electric heat require a 1-in. clearance for the first 24 in. of ductwork.

Outlet grilles must not lie directly below unit discharge. NOTE: A 90-degree elbow must be provided in the ductwork

to comply with UL (Underwriters’ Laboratories) codes for use with electric heat.

WARNING:

For vertical supply and return units, tools or parts could drop into ductwork and cause an injury. Install a 90 degree turn in the return ductwork between the unit and the conditioned space. If a 90 degree elbow cannot be installed, then a grille of sufficient strength and density should be installed to prevent objects from falling into the conditioned space. Due to electric heater, supply duct will require 90 degree elbow.

IV. STEP 4 — MAKE UNIT DUCT CONNECTIONS

Unit is shipped for thru-the-bottom duct conn ections. Ductwork openings a re shown in Fig. 6. Fi eld-fabricate d concentric ductwork may be connected as shown i n Fig. 7 and 8. Attach all ductwork to roof curb and roof curb basepans. Refer to installation instructions shipped with accessory roof curb for more information.

V. STEP 5 — TRAP CONDENSATE DRAIN

See Fig. 4, 5, and 9 for drain location. Plug is provided in drain hole and must be removed when unit is operating. One

/4-in. half-coupling is provided inside unit evaporator section for condensate drain connection. An 8 diameter nipple and a 2-in. x coupled to standard

/4-in. diameter pipe nipple are

/4-in. diameter elbows to provide a

/2 in. x 3/4-in.

straight path down through holes in unit base rails (see Fig. 10). A trap at least 4-in. deep must be used.

NOTE:

Do not drill in this area, as damage to basepan may result in

water leak.

Fig. 6 — Air Distribution — Thru-the-Bottom

(551A180 and 240 Shown)

Shaded area indicates block-off panels.

NOTE:

Dimension A, A′ and B, B′ are obtained from field-supplied ceil-

ing diffuser.

CAUTION:

units without electric heat. Personal injury or unit damage may result.

Concentric ducts may only be installed on

Fig. 8 — Concentric Duct Details

NOTE:

Do not drill in this area, as damage to basepan may result in

water leak.

Fig. 7 — Concentric Duct Air Distribution

(551A180 and 240 Shown)

Fig. 9 — Condensate Drain Details

(551A155 Shown)

—7—

Fig. 10 — Condensate Drain Piping Details

VI. STEP 6 — MAKE ELECTRICAL CONNECTIONS

A. Field Power Supply

Unit is factory wired for voltage sh own on nameplate. When installing units, provide a disconnect, per NEC

(National Electrical Code) requirements, of adequate size (Table 2). Electrical heater data is shown in Table 3.

All field wiring must comply with NEC and local requirements.

Route power lines through control box access panel or unit basepan (Fig. 4 and 5) to connections as shown on unit wiring diagram and Fig. 11.

Operating voltage to compressor must be within voltage range indicated on unit nameplate. On 3-phase units, voltages between phases must be balanced within 2% and the current must be balanced within 10%.

IMPORTANT: If the supply voltage phase imbalance is more than 2%, contact your local electric utility company immediately.

Unit failure as a res ult of ope ra tio n o n imp ro per line volt age or excessive phase imbalance constitutes abuse and may cause damage to electrical components.

B. Field Control Wiring

Install a Bryant-approved accessory thermostat assembly according to the installation instruct ions included with the accessory. Locate thermostat assembly on a solid wall in the conditioned space to sense average temperature.

Route thermostat cable or equivalent single leads of colored wire from subbase terminals through conduit in uni t to lowvoltage connections as shown on unit label wiring diagram and in Fig. 12.

NOTE: For wire runs up to 50 ft, use no. 18 AWG (American Wire Gage) insulated wire (35 C minimum). For 50 to 75 ft, use no. 16 AWG insulated wire (35 C minimum). For over 75 ft, use no. 14 AWG insulated wire (35 C minimum). All wire larger than no. 18 AWG cannot be directly connected to the thermos tat and wi ll req uire a j unction box and s plice a t the thermostat.

Set heat anticipator settings as indicated in Table 4. Settings may be changed slightly to pr ovide a greater degree of comfort for a particular installation.

CAUTION: The correct power phasing is critical in the operation of the scroll compressors. An incorrect phasing will cause the compressor to rotate in the wrong direction. This m ay lead to premature compres sor failure.

Use the following formula to determine the percentage of voltage imbalance.

Percentage of Voltage Imbalance

= 100 x

max voltage deviation from average v oltage

average voltage

EXAMPLE: Supply voltage is 460-3-60.

AB = 452 v BC = 464 v AC = 455 v

Average Voltage =

455 + 464 + 455

1371

= 457

Determine ma ximum 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 voltage imbalance:

Percentage of Voltage Imbalance = 100 x

7 457

= 1.53%

This amount of phase imbalance is satisfactory as it is below the maximum allowable 2%.

UNIT 551A

All

EQUIP — GND — kcmil —

Equipment Ground Code Thousand Circular Mils

Fig. 11 — Field Power Wiring Connections

REMOVABLE JUMPER

RED

Fig. 12 — Field Control Thermostat Wiring

TB1 MAXIMUM WIRE SIZE

VOLTAGE

208/230 460

350 kcmil 2/0

LEGEND

NEC —

TB —

THERMOSTAT ASSEMBLY

Y1 Y2

BLU

UNIT LOW-VOLTAGE CONNECTIONS

W1Y2

PNK

National Electrical

Terminal Block

ORN

VIO

BLK

BRN

WHT

—8—

UNIT 551A

155

(Standard

IFM)

155

(Optional

IFM)

180

240

Table 2 — Electrical Data

NOMINAL

VOLTAGE

(3 Ph,

60 Hz)

208/230 187 253 20.7 156 19.3 123 3 0.5 1.7 2.9

460 414 508 10 70 10 62 3 0.5 0.8 2.9 4.2

208/230 187 253 20.7 156 19.3 123 3 0.5 1.7 3.7

460 414 508 10 70 10 62 3 0.5 0.8 3.7 4.8

208/230 187 253 32.1 195 20.7 156 3 0.5 1.7 5.0

460 414 508 16.4 95 10 70 3 0.5 0.8 5.0 7.9

208/230 187 253 42 239 33.6 225 2 1 6.6 7.5

460 414 508 19.2 125 17.3 114 2 1 3.3 7.5 13.0

VO LTAG E

RANGE

Min Max RLA LRA RLA LRA Qty Hp FLA (ea) Hp FLA FLA LRA kW FLA MCA MOCP†

COMPRESSOR

No. 1 No. 2

OFM IFM

POWER

EXHAUST

—— — — 59/ 59 70/ 70

4.6 18.8 ——64/ 63 80/ 80 ——14/19 39/ 45 60/ 67 70/ 70

4.6 18.8 14/19 39/ 45 66/ 73 80/ 80

8.8/

8.4

——26/34 71/ 82 100/113 100/125

4.6 18.8 26/34 71/ 82 106/119 110/125 ——42/56** 117/135 157/146 175/175

4.6 18.8 42/56** 117/135 163/151 175/175 —— — — 29 35

2.3 6.0 —— 31 40 —— 15 18 29 35

2.3 6.0 15 18 31 40 —— 32 39 54 60

2.3 6.0 32 39 57 60 —— 55** 66 71 80

2.3 6.0 55** 66 74 80 —— — — 61/ 61 80/ 80

4.6 18.8 ——65/ 66 80/ 80 ——14/19 39/ 45 62/ 70 80/ 80

4.6 18.8 14/19 39/ 45 68/ 76 80/ 80

11.0/

10.5 ——26/34 71/ 82 102/116 110/125

4.6 18.8 26/34 71/ 82 108/122 110/125 ——42/56** 117/135 159/149 175/175

4.6 18.8 42/56** 117/135 165/155 175/175 —— — — 30 35

2.3 6.0 —— 32 40 —— 15 18 30 35

2.3 6.0 15 18 32 40 —— 32 39 55 60

2.3 6.0 32 39 58 60 —— 55** 66 72 80

2.3 6.0 55** 66 75 80 —— — — 82/ 82 110/110

4.6 18.8 ——86/ 86 110/110 ——26/34 71/ 82 109/122 110/125

15.8/

4.6 18.8 26/34 71/ 82 114/128 125/150

15.8 ——42/56 117/135 166/155 175/175

4.6 18.8 42/56 117/135 172/161 175/175 ——56/75** 156/180 176/200 200/225

4.6 18.8 56/75** 156/180 182/206 200/225 —— — — 41 50

2.3 6.0 —— 43 50 —— 32 39 59 60

2.3 6.0 32 39 62 70 —— 55 66 76 90

2.3 6.0 55 66 79 90 —— 80** 96 106 125

2.3 6.0 80** 96 109 125 —— — — 124/124 150/150

4.6 18.8 ——129/129 150/150 ——26/34 71/ 82 124/134 150/150

4.6 18.8 26/34 71/ 82 129/140 150/150

25.0/

25.0 ——42/56 117/135 178/166 200/175

4.6 18.8 42/56 117/135 183/172 200/175 ——56/75** 156/180 187/211 200/225

4.6 18.8 56/75** 156/180 193/217 200/225 —— — — 61 80

2.3 6.0 —— 63 80 —— 32 39 65 80

2.3 6.0 32 39 68 80 —— 55 66 82 90

2.3 6.0 55 66 85 90 —— 80** 96 112 125

2.3 6.0 80** 96 115 125

ELECTRIC

HEAT*

(See Legend on page 10.)

POWER

SUPPLY

—9—

FLA — HACR— IFM — LRA — MCA — MOCP— NEC — OFM — RLA —

*Heater capacity (kW) is based on heater voltage of 208 v, 240 v, and

†Fuse or HACR circuit breaker.

**Heaters are field installed only.

NOTES:

1. In compliance with NEC requirements for multimotor and combina-

Full Load Amps Heating, Air Conditioning and Refrigeration Indoor (Evaporator) Fan Motor Locked Rotor Amps Minimum Circuit Amps Maximum Overcurrent Protection National Electrical Code Outdoor (Condenser) Fan Motor Rated Load Amps

480 v. Heaters are rated at 240 v, or 480 v. If power distribution voltage to unit varies from rated heater voltage, heater kW will vary accordingly.

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

Unbalanced 3-Phase Supply Voltage

Never operate a motor where a phase imbalance in supply voltage is greater than 2%.

of voltage imbalance. % Voltage Imbalance

= 100 x

LEGEND

Use the following formula to determine the percent

max voltage deviation from average voltage

average voltage

Example: Supply voltage is 460-3-60.

AB = 452 v BC = 464 v AC = 455 v

= 457

7 457

452 + 464 + 455

1371

Average Voltage =

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

This amount of phase imbalance is satisfactory as it is below the maximum allowable 2%.

IMPORTANT:

contact your local electric utility company immediately.

3. MCA calculation for units with electric heaters over 50 kW = (1.25 x IFM amps) + (1.00 x heater FLA).

= 1.53%

If the supply voltage phase imbalance is more than 2%,

Table 3 — Electric Resistance Heater Data

UNIT

551A

*Maximum number of stages using accessory low-ambient kit or head pressure control device and low-ambient kit.

NOTE:

208 230 240 460 480 Cfm L/s 208 230 240 460 480

14 17 19 14 15 1 100 1

155

26 31 34 30 32 2 50/50 2 71.3 78.9 82.3 37.3 39.0 42 52 56 50 55 2 33/67 3 117.0 129.4 135.0 63.3 66.1 26 31 34 30 32 2 50/50 2

180

42 52 56 50 55 2 33/67 3 117.0 129.4 135.0 63.3 66.1 56 69 75 73 80 2 50/50 4 155.9 172.4 179.9 92.0 96.0 26 31 34 30 32 2 50/50 2

240

42 52 56 50 55 2 33/67 3 117.0 129.4 135.0 63.3 66.1 56 69 75 73 80 2 50/50 4 155.9 172.4 179.9 92.0 96.0

Heaters are rated at 240, and 480 v.

HEATER kW

Unit Voltages Heating Cfm

HEATER

STAGES

% HEAT

PER

STAGE

MAXIMUM

STAGES*

MINIMUM

39.3 43.4 45.3 17.2 17.9

3750 1770

71.3 78.8 82.3 37.3 39.0

3750 1770

71.3 78.8 82.3 37.3 39.0

5000 2360

HEATER AMPS

—10—

C. Optional Non-Fused Disconnect

CONTROL MODULE

ACTUATOR

ECONOMI$ER

On units with the optional non-fused disconnect, incoming power will be wired into the disconnect switch. Refer to Fig. 13 for wiring for 100 and 200 amp disconnect switches. Units with an MOCP (maximum overcurrent protection) under 100 will use the 100 amp disconnect switch. Units with an MOCP over 100 will use the 200 amp disconnect switch. Refer to the applicable disconnect wiring diagram.

To prevent breakage during s hipping, the disconne ct han dle and shaft are shipped and packaged inside the unit control box. Install the disconnect handle before unit operation. To install the handle and shaft, perform the following procedure:

1. Open the co nt rol b ox do or and remove the handle and shaft from shipping location.

2. Loosen the Allen bolt located on the disconnect switch. The bo lt is locate d on the square hole and is used to hold the shaft in place. The shaft cannot be inserted until the Allen bolt is moved.

3. Insert the disconnect shaft into the square hole on the disconnect switch. The end of the shaft is specially cut and the shaft can only be inserted in the correct orientation.

4. Tighten the Allen bolt to lock the shaft into position.

5. Close the control box d oor.

6. Attach the handle to the external access door with the two screws provided. When the handle is in the ON position, the handle will be vertical. When the handle is in the OFF position, the handle will be horizontal.

7. Turn the handle to the OFF position and close the door. The handle should fit over the end of the shaft when the door is closed.

8. The handle must be in the OFF position to open the control box door.

D. Optional Convenience Outlet

On units with optional convenience outlet, a 115-v GFI (ground fault interrupt) convenience outlet re ce ptacle is provided for field wiring . F ield wir ing s ho uld be run th roug h th e

/8-in. knockout provided in the basepan near the return air

opening.

VII. STEP 7 — MAKE OUTDOOR-AIR INLET ADJUSTMENTS

A. Manual Outdoor-Air Damper

All units (except those equipped with a factory-installed economizer) have a manual outdoor-air damper to provide ventilation air. Damper can be preset to admit up to 25% outdoor air into return-air compartment. To adjust, loosen securing screws and move dampe r to desired setting. Then retighten screws to secure damper (Fig. 14).

B. Optional EconoMi$er

EconoMi$er Motor Control Module (Fig. 15-17) Set the ECONSP dial to the ‘‘D’’ setting (Fig. 16). The control

module is located on the EconoMi$er motor. See Fig. 15 and

17. Damper Vent Position Setting

1. Set fan switch at ON position (continuous fan operation) and close night switch if used.

2. Set system selector switch to OFF position.

3. Turn Min Pos (%) dial slowly until dampers assume desired vent position. Do not manually operate

EconoMi$er motor since damage to motor will result.

Fig. 14 — 25% Outdoor-Air Section Details

6T3 4T2 2T1 LOAD

5L3 3L2 1L1 LINE

NOTE:

The disconnect takes the place of TB-1 as shown on the unit

wiring diagram label and the component arrangement label.

Fig. 13 — Optional Non-Fused Disconnect Wiring

Fig. 15 — EconoMi$er Damper Assembly

— End View

—11—

Table 4 — Heat Anticipator Settings

UNIT 551A

155-240

*Heater kW is based on heater voltage of 208 v, 240 v, or 480 v.

UNIT

VO LTAG ES

208/230-3-60

460-3-60

kW* STAGE 1 STAGE 2

14/19 .40 — 26/34 .40 .66 42/56 .66 .40 56/75 .66 .66

32 .40 .40 55 .40 .66 80 .66 .66

Fig. 16 — EconoMi$er Control Module

Adjustment Potentiometers

CONTROL MODULE ACTUATOR

Fig. 17 — EconoMi$er Control Module Location

VIII. STEP 8 — INSTALL OUTDOOR-AIR HOOD

The same type of factory-installed hood is used on units with 25% air ventilation and units with an EconoMi$er.

NOTE: The hood top panel, upper and lower filter retainers, hood drain pan, baffle (180-240), and filter support bracket are secured opposite the condenser end of the unit. The screens, hood side panels, remaining section of filter support bracket, seal strip, and a ll other har dware are in a package located inside the return-air filter access panel (Fig. 18).

1. Attach seal strip to upper filter retainer. See Fig. 19.

2. Assemble hood top panel and side panels, upper filter retainer, and hood drain pan (Fig. 20).

3. Secure lower filter retainer and long section of filter support bracket to unit. See Fig. 20. Leave screws loose on size 180 and 240 units.

4. Slide baffle (size 180 and 240 units) behind lower filter retainer and tighten screws.

5. Loosen sheet metal screws for base unit top panel located above outdoo r-air inlet opening, and rem ove screws for hood side panels located on the sides of the outdoor-air inlet opening.

6. Match notches in hood top panel to unit top panel screws. Insert hood flange between unit top panel flange and unit. Tighten screws.

7. Hold hood side panel flanges flat against unit, and install screws removed in Step 5.

8. Insert outdo o r-air inlet screens and spacer in c ha nne l created by lower filter retainer and filter support bracket.

9. Attach remaining short section of filter support bracket.

A. Outdoor Air Enthalpy Sensor Installation

Perform the following procedure to install the outdoor air enthalpy sensor (part no. CROUTENT001A00).

1. Remove the outdoor air temperature sensor cover. See Fig. 21. Save cover and screws.

2. Disconnect the wiring from the installed outdoor air temperature sensor. See Fig. 22.

3. Use a

/4-in. nut driver to remove the 2 screws securing the outdoor air temperature sensor to the sheet metal.

4. Mount the outdoor air enthalpy sensor in the outdoor air temperature sensor location using the screws removed in Step 3.

5. Connect the outdoor air enthalpy sensor wiring harness to the EconoMi$er control module and sensor.

6. Re-install sensor cover saved from Step 1.

B. Return Air Temperature Sensor or Return Air Enthalpy Sensor Installation

Perform the following procedure to install the return air temperature sensor (part no. CRRETTMP001A00) or return air enthalpy sensor (part no. CRRETENT001A00).

1. Attach the sensor to the mounting bracket using 2 self-tapping

/2-in. screws provi ded .

2. Mount the bracket to the inside of the return air

opening flange using a

/4-in. nut driver and 2 no.

6 sheet metal screws.

NOTE: The sensor must be mounted in an upright position.

3. Feed the sensor wiring through the bushing in EconoMi$er t o sec ur e wires.

4. Route sensor wiring harness from sensor to EconoMi$er control module. Secure wiring harness to the original har ness using tie wraps.

5. Wire the sensor to the EconoMi$er control module. See Fig. 23 and 24.

—12—

Fig. 18 — Outdoor-Air Hood Component Location

SENSOR COVER

OUTSIDE AIR SENSOR

MOUNTING SCREW

WIRING HARNESS

SENSOR WIRING CONNECTIONS

Fig. 19 — Seal Strip Location

(Air Hood Cross-Sectional View)

BAFFLE (180 AND 240 ONLY)

LOWER FILTER RETAINER

FILTER SUPPORT BRACKET

HOOD SIDE

HOOD TOP PANEL

HOOD DRAIN PAN

UPPER FILTER RETAINER

NOTE:

The outdoor-air hood comes with a baffle which is used on

180 and 240 units only; discard baffle for 155 units.

PANELS (2)

BAFFLE (180 AND 240 ONLY)

LOWER FILTER RETAINER

FILTER SUPPORT BRACKET

Fig. 20 — Outdoor-Air Hood Details

C. Commissioning

The EconoMi$er saves energy when it uses outdoor air to provide free cooling instead of mechanical air conditioning. The EconoMi$er switchov er strategy determines if the outdoor air is suitable for free cooling. The EconoMi$er chooses the switchover strategy with the most energy savings, provided that the required sensors are connected and functioning normally.

IMPORTANT: If a sensor stops functioning normally (becomes unreliable), the EconoMi$er switches to the next best strategy.

Fig. 21 — Outdoor-Air Sensor Location

Fig. 22 — Outdoor-Air Sensor Details

Refer to Table 5 to determine the sensors required for each strategy.

Differential Enthalpy Switchover Strategy The differential enthalpy switchover strategy must be

selected manually, if required. To enable, press and hold the CONFIG button for 30 seconds, then release. The LED will flash twice to indicate the change of configuration.

To return to single enthalpy mode, press and hold the CONFIG button for 30 seconds. The LED will flash once to indicate the change of configuration.

D. Discharge Air Thermistor (DAT)

The discharge air thermistor is factory-mounted on the supply-fan housing in the fan section of the unit. The DAT is factory-wired to the EconoMi$er Control Module.

E. CO

Control Setup

If a CO

sensor is not bei ng us ed, proc ee d to the n ext s ectio n.

If a CO2 sensor is being used, perform the following:

1. Determin e the v alue at which y ou w ant the minimu m position of the dam pers to begin opening to allow a greater amount of outdoor air to enter. The range is 800 to 1,400 ppm.

2. Locate the CO

SP (PPM) potentiometer and adjust

to the desired set point. See Fig. 16.

—13—

F. Mechanical Cooling Lockout

Determine the outdoor-air temperature at which you want the mechanical cooling (compressors) to be disabled. Locate the mechanical cooling lockout (MECH CLG LOCKOUT) potentiometer. To disable this feature, turn the potentiometer counterclockwise (CCW) to the OFF position. Otherwise, set the value between 10 and 60 F. Mechanical cooling will not operate when the ou tdoor air temperat ure is below this value. See Fig. 16.

Table 5 — EconoMi$er Switchover Control Strategy

ECONOMI$ER SWITCHOVER STRATEGY

Dry Bulb

Single Enthalpy

Differential Temperature

Differential Enthalpy*

*Must be selected manually.

Outdoor Air Temperature Outdoor Air Enthalpy Return Air Temperature Return Air Enthalpy

Table 6 — Changeover Set Points

SETTINGS A B C D Dry Bulb (°F) Single Enthalpy* (Btu/lb) Differential Temperature*

(°F, Not Adjustable) Differential Enthalpy*

(Btu/lb, Not Adjustable)

*Field-installed accessory.

73 69 66 63 27 25 24 22

2222

1111

G. Dry Bulb Changeover Set Up

Determine the dry bulb changeover set poin t from Table 6. The settings are A, B, C and D. Locate the ECON SP potentiometer and set the dry bulb changeover set point. See Fig. 16. When the OAT is above this set point, the damper is limited to minimum position setting.

If a potentiometer fails, its setting will default to the values in Table 7.

SENSORS REQUIRED

Table 7 — Default Potentiometer Settings

POTENTIOMETER DEFAULT SETTING

CO2 SP (PPM) MECH CLG LOCKOUT ECON SP MIN POS (%)

1,000

50 F

COM — DAT — DM — GND — OAH — OAT — POT — RAH — RAT — REM —

LEGEND

Common Discharge Air Thermistor Damper Motor Ground Outdoor-Air Enthalpy Sensor Outdoor-Air Temperature Sensor Potentiometer Return-Air Enthalpy Sensor Return-Air Temperature Sensor Remote

*OAT sensor shipped with economizer option. OAH, RAT, RAH and CO

Fig. 23 — Typical EconoMi$er Wiring

are field-installed accessories.

—14—

H. Ventilation Air (Minimum Position Set Up)

If ventilatio n a i r is n ot r e qui re d, s ki p th is s ect io n. I f ven ti la tion air is requir ed, perform the following:

1. The indoor fan must be on to set the ventilation air. Either put the thermostat in the continuous fan mode or jumper the R and G te rminals at the ro oftop unit connection board.

2. Locate the minimum position (MIN POS) potentiometer. Turn the potentiometer full CCW to fully close the outdoor air dampers. Turn the potentiometer gradually clockwise (CW) to the desired position. See Fig. 16.

3. Replace the filter access panel. See Fig. 18. Ensure the filter access panel is securely engaged.

4. Calculate the minimum airflow across the EconoMi$er.

a. Calculate % of outside air using the following

formula. % Outdoor air through EconoMi$er % Outdoor

air

Mixture Temp – Return Air Temp

Outdoor Temp – Return Air Temp

b. Multiply total CFM by percentage outdoor air,

this gives outdoor air volume in CFM.

WARNING:

Personal Injury Hazard.

Avoid possible

injury by keeping fingers away from damper blades.

IX. STEP 9 — INSTALL ALL ACCESSORIES

After all the factory-installed options have been adjusted, install all field-instal led accessories. Refer to the accessory installation instructions included with each accessory.

A. Motormaster® I Control Installation (551A155 and 180 Only)

Install Field-Fabricated Wind Baffles Wind baffles must be fi eld-fabricat ed for all units to en sure

proper cooling cycle oper ation at low ambient temperatu res. See Fig. 25 for baffle de tails. Use 20-gage, galvani zed sheet metal, or similar corrosion-resistant metal for baffles. Use field-supplied screws to attach baffles to unit. Screws should

/4-in. diameter and 5/8-in. long. Dri ll requ ired screw ho les

for mounting baffles.

CAUTION:

To avoid damage to the refrigerant coils and electrical components, use recommended screw sizes only. Use care when drilling holes.

Outdoor Air Enthalpy

CROUTENT001A00

OAT COM OAH +15V RAT COM RAH +15V

(+)

COM DAT COM REM POT COM LED COM

Tan Violet White Red

Violet

C O M

Remote

Minimum Position

1k ohm Potentiometer

O U TT

Unoccupied Control

(Part number on the control

must be AD-DME1701-1

or AD-DME1711-1.)

Unoccupied

Contact

24 VAC must be present

on BI for the system to be

Violet

470 ohm

5watt

Resistor

unoccupied.

Return Air Enthalpy

CRRETENT001A00

CO2 Sensors:

CRCDXSEN004A00

NOT

USED

2to10VDCat 0 to 2000 ppm

Line

20 VA

24 VAC

Voltage

20 mA LED

Remote

LED

Field-supplied Wiring Wiring Included

Fig. 24 — Typical EconoMi$er Sensor Wiring

—15—

Install Motormaster® I Controls Only one Motormaster I control is required per unit. The

Motormaster I control must be used in c onjunction with the Accessory 0° F Low Ambient Kit (purchased separately). The Motormaster I device contro ls outdoor fan no. 1 while outdoor fans no. 2 and 3 are sequenced off by the Accessory 0° F Low Ambient Kit.

Accessory 0° F Low Ambient Kit — Install the Accessory 0° F Low Ambient Kit per instruction supplied with accessory.

Sensor Assembly — Install the sensor assembly in the location shown in Fig. 26.

Motor Mount — To ensure proper fan height, replace the existing motor mount with the new motor m ount provided with accessory.

Transformer (460-v Units Only) — On 460-volt units a transformer is required. The transformer is provided with the accessory and must be field-installed.

Motormaster I Control — Recommended mounting location is on the inside of the panel to the left of the control box. The control should be mounted on the inside of the panel, vertically, with leads prot ruding from bottom of extrusion.

B. Motormaster III Control Installation (551A240 Only)

Install Field-Fabricated Wind Baffles Wind baffles must be field-fabricated for all units to ensure

proper cooling cycle operation at low ambient temperatures. See Fig. 25 for ba ffle detai ls. Use 20-gage, g alvanized s heet metal, or similar corrosion-resistant metal for baffles. Use field-supplied screws to attach baffles to unit. Screws should

/4-in. diameter and 5/8-in. long. Drill r equir ed scre w holes

for mounting baffles.

NOTE:

Dimensions in ( ) are in mm.

Fig. 25 — Wind Baffle Details

CAUTION:

To avoid damage to the refrigerant coils and electrical components, use recommended screw sizes only. Us e care when drilling holes.

Replace Outdoor Motor Replace outdoor fan motor no. 1 with motor included in

accessory kit. Existing motor is not Motormaster® III compatible.

Install Motormaster III Controls Only one Motormaster III control is required per unit. Sensor — Install the se nsor for thermistor input con trol in

the location shown in Fig. 26. Connect sensor leads to the purple and grey c ontrol si gnal leads o n the Motor master III control.

Signal Selection Switch — Remove the cover of the M otormaster III control. Set t he switch to accept the thermistor sensor input signal. Set the frequency to match the unit power supply (60 Hz).

Motormaster III Control — Recommended mounting location is beneath the control box, mounted to the partition that separates the control box section from the indoor section.

NOTE: If unit power is supplied through the roof curb and basepan of the unit, mount the Motormaster III contro l on the corner post adjacent to the conduit running from the basepan to the bottom of the control box.

X. STEP 10 — INSTALL HUMIDISTAT FOR OPTIONAL PERFECT HUMIDITY™ DEHUMIDIFICATION PACKAGE

Perfect Humidity dehumidification package operation can be controlled by field installation of a Bryant-approved humidistat. To install the humidistat perform the following procedure:

1. Locate humidistat on a solid interior wall in the conditioned space. Location should be a well ventilated area to sense average humidity.

2. Route thermostat cable or equivalent single leads of colored wire from humidistat termi nals through conduit in unit to the low voltage connection on the 2-pole ter minal strip (TB3 ) as shown in Fig. 27 and Fig. 28.

—16—

MOTORMASTER SENSOR

NOTES:

1. All sensors are located on the eighth hairpin up from the bottom.

2. Field-installed tubing insulation is required to be installed over the TXV bulb and capillary tube for proper operation at low ambients. Tubing insulation is only required on the portion of suction line located between indoor and outdoor section.

LOCATION

HAIRPIN END

Fig. 26 — Motormaster® I and Motormaster III

Sensor Locations

Fig. 28 — Typical Perfect Humidity Dehumidification

Package Control Box

CB — LLSV — LPS — TB — TRAN —

LEGEND

Circuit Breaker Liquid Line Solenoid Valve Low-Pressure Switch Terminal Block Transformer

Fig. 27 — Typical Perfect Humidify™ Dehumidification Package

Humidistat Wiring Schematic (460V Unit Shown)

—17—

START-UP

Use the following information and Start-Up Checklist on page CL-1 to check out unit PRIOR to start-up.

I. UNIT PREPARATION

Check that unit has been installed in accordance with these installation instructions and all applicable codes.

II. COMPRESSOR MOUNTING

Compressors are internally spring mounted. Do not loosen or remove compressor holddown bolts.

III. REFRIGERANT SERVICE PORTS

Each refrigerant system has a total of 3 Schrader-type service gage ports. One port is located on the suction line, one on the compressor discharge line, and one on the liquid line. In addition Schrader-type valves are located underneath the lowpressure switches. Be sure that caps on the ports are tight.

IV. COMPRESSOR ROTATION

It is important to be c ertain the c ompressors are rotating in the proper direction. To determine whether or n ot compressors are rotating in the proper direction:

1. Connect ser vice gage s to suctio n and dis charge pres sure fittings.

2. Energize the compressor.

3. The suction pressu re should drop and th e discharge pressure should rise, as is normal on any start-up.

If the suction pressure does not drop and the discharge pressure does not rise to normal levels:

1. Note that the evaporator fan is probably also rotating in the wrong direction.

2. Turn off power to the unit.

3. Reverse any two of the incoming power leads.

4. Turn on power to the compressor.

The suction and discharge pressure levels should now move to their normal start-up levels.

NOTE: When compressors are rotati ng in the wrong direction, the unit will have increased noise levels and will not provide heating and cooling.

After a few minutes o f re vers e o per ation , th e s cro ll co m pressor internal overload protection will open, which will activate the unit’s lockout and requires a manual reset. Reset is accomplished by turning the thermostat on and of f.

V. INTERNAL WIRING

Check all electrical connections in unit control boxes; tighten as required.

VI. CRANKCASE HEATERS

Heaters are energized as long as there is power to unit and compressor is not operating.

IMPORTANT: Unit power must be on for 24 hours prior to start-up. Otherwise, damage to compressor may result.

VII. EVAPORATOR FAN

Fan belt and variable pulleys are factory installed. Remove tape from the fan pulley. See Table 8 for Air Quantity Limits . See Tables 9-12 for Fan Performance data. Be sure that fans rotate in the proper direction. See Tables 13 and 14 for Static Pressure information for accessories and options. See Table 15 for fan rpm at various fan motor pulley settings. See Table 16 for Evaporator-Fan Motor Specifications. To alter fan performance, see Evaporator-Fan Performance Adjustment section, page 26.

Table 8 — Air Quantity Limits

UNIT

551A

155 180 240

MINIMUM CFM MAXIMUM CFM

3600 6,000 4500 7,500 6000 10,000

VIII. CONDENSER FANS AND MOTORS

Condenser fans and motors are factory set. Refer to Condenser-Fan Adjustment section (page 28) as required. Be sure that fans rotate in the correct direction.

IX. RETURN-AIR FILTERS

Check that correct filters are installed in filter tracks. See Table 1. Do not operate unit without return-air filters.

X. OUTDOOR-AIR INLET SCREENS

Outdoor-air inlet screen s must be in place bef ore operating unit.

XI. ACCESSORY ECONOMI$ER ADJUSTMENT

Remove filter access panel. Check that outdoor-air damper blades are closed and return-air damper blades are open.

EconoMi$er operation and adjustment is described in Base Unit Operation and EconoMi$er Adjustment sections (this page and page 28), respectively.

XII. BASE UNIT OPERATION

A. Cooling, Units Without EconoMi$er

When thermos tat calls for cool ing, terminals G and Y1 are energized. The indoor (evaporator) fan contactor (IFC), and compressor contactor no. 1 (C1) are energized and evaporator-fan motor, compressor no. 1 and condenser fans start. The condenser-fan motors run continuously while unit is cooling. If the thermostat calls for a second stage of cooling by energizing Y2, compressor contactor no. 2 (C2) is energized and compressor no. 2 starts.

B. Heating, Units Without EconoMi$er (If Accessory or Optional Heater is Installed)

Upon a call for heating through terminal W1, IFC and heater contactor no. 1 (HC1) are energized. On units equipped for 2 stages of heat, when additional heat is needed, HC2 is energized through W2.

C. Cooling Units With EconoMi$er

When the OAT is above the ECON SP set point and the room thermostat calls for Stage 1 cooling (R to G + Y1), the indoorfan motors (IFM) i s energized and the Econ oMi$er damper modulates to minimum position. The compressor contactor and OFC are energized to start the comp ressor and outdo orfan motor (OFM). After the thermostat is satisfied, the damper modulates to the fully closed position when the IFM is deenergized.

When the OAT is below the ECON SP setting and the room thermostat calls for Stage 1 cooling (R to G + Y1), the EconoMi$er modulates to the minimum position when the IFM is energized. The Econ oMi$er provides Sta ge 1 of cooling by modulating the return and outdoor air dampers to maintain a 55 F supply air set point. If the supply-air temperature (SAT) is greater than 57 F, the Econ oMi$er modulates open, allowing a greater amount of outdoor air to enter the unit. If the SA T drops bel ow 53 F, the outdoo r air d amp er modulates closed to reduce the amou nt of outd oor air. When the SAT is between 53 and 57 F, the EconoMi$er maintains its position.

—18—

If outdoor air alone cannot satisfy the cooling requirements of the conditione d space, and the OAT is above the MECH CLG LOCKOUT set point, the EconoMi$er integrates free cooling with mechanic al coo lin g. This is acco mpl ishe d b y the strategies below.

NOTE: Compressors have a two-minute Minimum On and Minimum Off, which are accomplished by the strategies below.

1. If Y1 is energized, and th e room thermosta t calls for Y2 (2-stage thermostat), the compressor and OFC are energized. The position of the EconoMi$er damper is maintained at its current value.

2. If Y1 is ene rgized for mor e than 2 0 minute s , and Y2 is not energized (whether or not a 2-stage thermostat is used), the compressor and OFC are energized. The position of the EconoMi$er damper is maintained at its current value.

3. If Y1 is energized, and compressor no. 1 is already energized (see S tep 2) and the ro om thermosta t calls for Y2, compressor no. 1 continues to operate. If Y2 remains energized for more than 20 minutes, compressor no. 2 is energized.

NOTE: Compressor no. 2 cannot be energized unless there is a signal for Y2 from the space thermostat.

4. If compressor no. 2 is energized, and the Y2 signal from the thermostat is satisfied, compressors 1 and 2 are deenergized. Re-asserting Y2 will start compressor no. 1 and (after a 20-minute interstage delay) compressor no. 2.

5. If compresso r no. 1 is energized and the thermostat is satisfied, compressor no. 1, the OFM, and IFM are deenergized and the EconoMi$er modulates closed.

When the OAT is below the MECH CLG LOCKOUT set point, the compressors re main off.

D. Freeze Protection Thermostat(s)

A freeze protection thermostat (FPT) is located on the top and bottom of the evaporator coil. It detects frost build-up and turns off the compress or, allowi ng the coil to clear. Once frost has melted, the compressor can be reenergized by resetting the compressor lockout.

E. Heating, Units With EconoMi$er (If Accessory or Optional Heater is Installed)

When the room the rmostat calls for heat, the heat ing controls are energized as described in the Heating, Units Without EconoMi$er section. The IFM is energized and the EconoMi$er damper modulates to the minimum position. When the thermostat is satisfied, the damper modulates closed.

F. Units With Perfect Humidity™ Dehumidification Package

When thermostat calls for cooling, terminals G and Y1 and/ or Y2 and the compressor contactor C1 and/or C2 are energized. The indoor (evaporator) fan motor (IFM), compressors, and outdoor (condenser) fan motors (OFM) start. The OFMs run continuously while the unit is in cooling. As shipped

from the factory, both Perfect Humidity dehumidification circuits are always energized.

If Perfect Humidity circuit modulation is desired, a fieldinstalled, w all- mou nted hu midi stat is re quired . If th e Perfect Humidity humidistat is installed and calls for the Perfect Humidity subcooler coil to operate, the humidistat internal switch closes. This energizes the 3-way liquid line solenoid valve coils (LLSV1 for circuit 1 and LLSV2 for circuit 2) of the Perfect Humidity circuits, forcing t he warm liquid refrigerant of the liquid line to enter the subcooler coils. See Fig. 29.

As the warm liquid passes through the subcooler coils, it is exposed to the cold supply airf low comi ng off the e vaporato r coils and the liquid is further cooled to a temperature approaching the evaporator coil leaving-air temperature. The state of the refrigerant leaving the subcooler coils is a highly subcooled liquid refrigerant. The liquid then enters a thermostatic expansion valve (TXV) where the liquid is dropped to the evaporator pressure. The TXVs can throttle the pressure drop of the liquid refrigerant and maintain proper conditions at the compressor suction valves over a wide range of operating conditions. The liquid proceeds to the evaporator coils at a temperature lower than normal cooling operati on. This low er temperatu re is what i ncreases the latent and sensible capacity of the evaporator coils.

The 2-phase refrige rant pass es th roug h the e vapo rator s an d is changed into a vapor. The air passing over the evaporator coils will become col der than during normal operation as a result of the colde r refrigeran t temperatures. However, as it passes over the subcooler coils, the air will be warmed, decreasing the sensible capacity and reducing the sensible heat of the roof- top unit.

As the refrigerant leaves the evaporator, the refrigerant passes a subcooler control low-pressure switch (S-LPS1 for circuit 1 or S-LPS2 for circuit 2) in the suction line. This lowpressure switch will deactivate the Perfect Humidity package when the suction pressure reaches 60 psig. The subcooler control low-press ure switch is an added safety device to protect against evaporator coil freeze-up during low ambient operation. T he subcooler control low-pressure switch will only deactivate the 3-way liquid line solenoid valve in the Perfect Humidity circuit. The compressors will continue to run as long as th ere is a call for cooling, regardles s of the position of the subcooler control low-pressure switch. The 3-way solenoid valve and th e Perfect Humidity package will be reactivated o nly when the call for co oling has been satisfied, the subcooler control low-pressure switch has closed above 80 psig, and a new call for cooling exists. The crankcase heaters on the scroll compressors provide additional protection for the compressors due to the additional refrigerant charge in the subcooler.

When the humidistat is satisfied, the humidistat internal switch opens, cutting power to and deenergizing the LLSVs. The refrigerant is routed back through the evap orators and the subcooler coils are removed from the refrigerant loops. When the thermostat is satisfied, C1 and C2 are deenergized and the comp ressors, IFM, a nd O FMs shut off. I f t he thermostat fan selector switch is in the ON position, the IFM will run continuously.

—19—

Table 9 — Fan Performance — 551A155 (With Standard Indoor Fan Motor)

551A155 (12 TONS)*

Available External Static Pressure (in. wg)

Cfm

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

3750 4000 4250 4500 4750 5000 5250 5500 5750 6000 6250

551A155 (12 TONS) (cont)*

Cfm

3750 4000 4250 4500 4750 5000 5250 5500 5750 6000 6250

Bhp — FIOP — Watts —

*Standard low-medium static drive range is 834 to 1064 rpm. Alternate

high-static drive range is 1161 to 1426. Other rpms require a fieldsupplied drive.

NOTES:

1. Maximum continuous bhp for the standard motor is 3.13. The max-

753 915 1.05 786 972 1.12 892 1170 1.35 991 1378 1.58 1084 1595 1.83 747 977 1.12 810 1090 1.25 911 1292 1.49 1007 1503 1.73 1097 1723 1.98 741 1041 1.20 835 1220 1.40 932 1426 1.64 1024 1640 1.89 1111 1863 2.14 761 1158 1.33 861 1360 1.56 954 1570 1.81 1043 1788 2.06 1127 2014 2.32 792 1305 1.50 887 1512 1.74 977 1726 1.99 1063 1948 2.24 1145 2177 2.50 823 1464 1.68 915 1676 1.93 1002 1894 2.18 1084 2120 2.44 1164 2352 2.70 855 1635 1.88 943 1852 2.13 1027 2075 2.39 1107 2304 2.65 1184 2539 2.92 887 1819 2.09 972 2041 2.35 1053 2268 2.61 1130 2501 2.88 ——— 920 2016 2.32 1002 2242 2.58 1079 2473 2.84 —————— 953 2226 2.56 1031 2457 2.83 1107 2692 3.10 —————— 986 2449 2.82 1062 2685 3.09 —————————

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

1172 1822 2.10 1256 2057 2.37 1337 2299 2.64 1414 2549 2.93 ——— 1182 1952 2.24 1264 2188 2.52 1343 2432 2.80 1418 2683 3.09 ——— 1194 2093 2.41 1274 2332 2.68 1351 2577 2.96 —————— 1208 2247 2.58 1286 2487 2.86 ————————— 1223 2412 2.77 1299 2655 3.05 ————————— 1240 2590 2.98 ————————————

— — —— — —— — —— — —— — — — — —— — —— — —— — —— — — — — —— — —— — —— — —— — — — — —— — —— — —— — —— — — — — —— — —— — —— — —— — —

Brake Horsepower Factory-Installed Option Input Watts to Motor

imum continuous watts is 2700. Do not adjust motor rpm such that motor maximum bhp and/or watts is exceeded at the maximum operating cfm.

0.2 0.4 0.6 0.8 1.0

Available External Static Pressure (in. wg)

1.2 1.4 1.6 1.8 2.0

LEGEND

2. Static pressure losses (i.e., EconoMi$er) must be added to external static pressure before entering Fan Performance table.

3. Interpolation is permissible. Do not extrapolate.

4. Fan performance is based on wet coils, clean filters, and casing losses. See Table 13 for accessory/FIOP static pressure information.

5. Extensive motor and drive testing on these units ensures that the full bhp and watts range of the motor can be utilized with confidence. Using your fan motors up to the watts or bhp rating shown will not result in nuisance tripping or premature motor failure. Unit warranty will not be affected.

6. Use of a field-supplied motor may affect wiring size. Contact your Bryant representative for details.

—20—

551A155 (12 TONS)*

Cfm

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

3750 4000 4250 4500 4750 5000 5250 5500 5750 6000 6250

551A155 (12 TONS) (cont)*

Cfm

3750 4000 4250 4500 4750 5000 5250 5500 5750 6000 6250

753 942 1.08 786 998 1.15 892 1192 1.37 991 1395 1.60 1084 1606 1.85 747 1006 1.16 810 1118 1.29 911 1315 1.51 1007 1520 1.75 1097 1733 1.99 741 1073 1.23 835 1248 1.44 932 1448 1.67 1024 1657 1.91 1111 1872 2.15 761 1191 1.37 861 1389 1.60 954 1593 1.83 1043 1804 2.07 1127 2022 2.33 792 1339 1.54 887 1541 1.77 977 1749 2.01 1063 1963 2.26 1145 2183 2.51 823 1499 1.72 915 1705 1.96 1002 1916 2.20 1084 2133 2.45 1164 2356 2.71 855 1671 1.92 943 1880 2.16 1027 2095 2.41 1107 2316 2.66 1184 2541 2.92 887 1854 2.13 972 2068 2.38 1053 2286 2.63 1130 2510 2.89 1205 2739 3.15 920 2050 2.36 1002 2268 2.61 1079 2490 2.86 1154 2717 3.12 1227 2948 3.39 953 2258 2.60 1031 2480 2.85 1107 2706 3.11 1179 2936 3.38 1249 3171 3.65 986 2480 2.85 1062 2706 3.11 1135 2935 3.38 1205 3169 3.64 1273 3406 3.92

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

1172 1825 2.10 1256 2051 2.36 1337 2284 2.63 1414 2523 2.90 1488 2768 3.18 1182 1954 2.25 1264 2181 2.51 1343 2415 2.78 1418 2655 3.05 1491 2901 3.34 1194 2094 2.41 1274 2323 2.67 1351 2558 2.94 1424 2799 3.22 1496 3045 3.50 1208 2246 2.58 1286 2476 2.85 1360 2713 3.12 1432 2955 3.40 1502 3202 3.68 1223 2410 2.77 1299 2642 3.04 1371 2880 3.31 1442 3123 3.59 1510 3372 3.88 1240 2585 2.97 1313 2819 3.24 1384 3059 3.52 1453 3304 3.80 1520 3554 4.09 1258 2773 3.19 1329 3009 3.46 1398 3250 3.74 1465 3497 4.02 1530 3748 4.31 1276 2972 3.42 1346 3211 3.69 1413 3455 3.97 1479 3703 4.26 ——— 1296 3185 3.66 1364 3426 3.94 1430 3671 4.22 —————— 1317 3410 3.92 1383 3653 4.20 ————————— 1339 3648 4.20 ————————————

0.2 0.4 0.6 0.8 1.0

1.2 1.4 1.6 1.8 2.0

Table

10 — Fan Performance — 551A155 (Wi

Available External Static Pressure (in. wg)

th Optional Indoor Fan Motor)

LEGEND

Bhp — FIOP — Watts —

*Standard low-medium static drive range is 834 to 1064 rpm. Alternate

high-static drive range is 1161 to 1426. Other rpms require a fieldsupplied drive.

NOTES:

1. Maximum continuous bhp for the optional motor is 4.38. The maxi-

Brake Horsepower Factory-Installed Option Input Watts to Motor

mum continuous watts is 3775. Do not adjust motor rpm such that motor maximum bhp and/or watts is exceeded at the maximum operating cfm.

2. Static pressure losses (i.e., EconoMi$er) must be added to external static pressure before entering Fan Performance table.

3. Interpolation is permissible. Do not extrapolate.

4. Fan performance is based on wet coils, clean filters, and casing losses. See Table 13 for accessory/FIOP static pressure information.

6. Use of a field-supplied motor may affect wiring size. Contact your Bryant representative for details.

—21—

551A180 (15 TONS)*

Cfm

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

4500 4800 5100 5700 6000 6300 6600 6900 7200 7500

551A180 (15 TONS) (cont)*

Cfm

4500 4800 5100 5700 6000 6300 6600 6900 7200 7500

753 1307 1.53 753 1307 1.53 784 1397 1.64 859 1635 1.92 928 1880 2.20 747 1384 1.62 747 1384 1.62 806 1563 1.83 878 1808 2.12 946 2060 2.42 741 1465 1.72 752 1500 1.76 828 1745 2.05 898 1996 2.34 964 2255 2.65 735 1659 1.95 805 1895 2.22 876 2156 2.53 942 2423 2.84 1004 2696 3.16 759 1854 2.18 832 2118 2.48 901 2388 2.80 965 2663 3.12 1026 2943 3.45 790 2088 2.45 860 2360 2.77 926 2638 3.09 988 2920 3.43 1048 3208 3.76 821 2340 2.74 888 2621 3.07 952 2906 3.41 1013 3196 3.75 1070 3491 4.10 852 2611 3.06 917 2900 3.40 979 3194 3.75 1038 3492 4.10 1094 3794 4.45 883 2903 3.40 946 3200 3.75 1006 3501 4.11 1063 3807 4.47 1118 4117 4.83 914 3215 3.77 975 3521 4.13 1033 3830 4.49 1089 4143 4.86 1142 4461 5.23

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

993 2133 2.50 1055 2394 2.81 1114 2662 3.12 1170 2938 3.45 1224 3220 3.78 1009 2319 2.72 1070 2585 3.03 1127 2859 3.35 1183 3139 3.68 1236 3427 4.02 1026 2521 2.96 1086 2794 3.28 1142 3073 3.60 1196 3359 3.94 1248 3650 4.28 1064 2975 3.49 1120 3260 3.82 1174 3551 4.17 1226 3848 4.51 1277 4151 4.87 1083 3228 3.79 1139 3520 4.13 1192 3817 4.48 1243 4119 4.83 1292 4427 5.19 1104 3501 4.11 1158 3799 4.46 1210 4102 4.81 1260 4410 5.17 1309 4724 5.54 1125 3791 4.45 1178 4095 4.80 1229 4405 5.17 1278 4720 5.54 1326 5039 5.91 1147 4101 4.81 1199 4412 5.18 1249 4728 5.55 1297 5050 5.92 ——— 1170 4431 5.20 1221 4749 5.57 1270 5072 5.95 —————— 1193 4781 5.61 1243 5107 5.99 —————————

0.2 0.4 0.6 0.8 1.0

1.2 1.4 1.6 1.8 2.0

Table 11 — Fan Perfor

Available External Static Pressure (in. wg)

ance

— 551A180

551A180 (15 TONS) (cont)*

Available External Static Pressure (in. wg)

Cfm

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

4500 4800 5100 5700 6000 6300 6600 6900 7200 7500

Bhp — FIOP — Watts —

*Standard low-medium static drive range is 873 to 1021 rpm. Alternate

high-static drive range is 1025 to 1200. Other rpms require a fieldsupplied drive.

NOTES:

1. Maximum continuous bhp for the standard motor is 6.13. The max-

1276 3509 4.12 1326 3805 4.46 1375 4107 4.82 1421 4414 5.18 1467 4728 5.55 1287 3721 4.36 1336 4020 4.72 1384 4326 5.07 1430 4638 5.44 1475 4955 5.81 1299 3949 4.63 1347 4253 4.99 1395 4563 5.35 1440 4879 5.72 ——— 1325 4458 5.23 1373 4772 5.60 1418 5091 5.97 —————— 1340 4741 5.56 1387 5060 5.93 ————————— 1356 5043 5.91 ————————————

— — —— — —— — —— — —— — — — — —— — —— — —— — —— — — — — —— — —— — —— — —— — — — — —— — —— — —— — —— — —

Brake Horsepower Factory-Installed Option Input Watts to Motor

imum continuous watts is 5180. Do not adjust motor rpm such that motor maximum bhp and/or watts is exceeded at the maximum operating cfm.

2.2 2.4 2.6 2.8 3.0

LEGEND

2. Static pressure losses (i.e., EconoMi$er) must be added to external static pressure before entering Fan Performance table.

3. Interpolation is permissible. Do not extrapolate.

4. Fan performance is based on wet coils, clean filters, and casing losses. See Table 13 for accessory/FIOP static pressure information.

6. Use of a field-supplied motor may affect wiring size. Contact your Bryant representative for details.

—22—

Table 12 —

551A240 (20 TONS)*

Cfm

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

6,000 6,500 7,000 7,500 8,000 8,500 9,000 9,500

10,000

551A240 (20 TONS) (cont)*

Cfm

6,000 6,500 7,000 7,500 8,000 8,500 9,000 9,500

10,000

551A240 (20 TONS) (cont)*

Cfm

6,000 6,500 7,000 7,500 8,000 8,500 9,000 9,500

10,000

Bhp — FIOP — Watts —

*Standard low-medium static drive range is 1002 to 1151 rpm. Alternate

high-static drive range is 1193 to 1369. Other rpms require a fieldsupplied drive.

NOTES:

1. Maximum continuous bhp for the standard motor is 9.47 (for 208-v units) and 10.33 (for 230 and 460-v units). The maximum continuous watts is 7915 (for 208-v units) and 8640 (for 230 and 460-v units). Do not adjust motor rpm such that motor maximum bhp and/or watts is exceeded at the maximum operating cfm.

753 2385 2.83 816 2579 3.06 884 2807 3.33 949 3040 3.61 1010 3277 3.89 793 2738 3.25 861 2959 3.51 925 3186 3.78 987 3418 4.05 1045 3653 4.33 844 3151 3.74 908 3372 4.00 968 3598 4.27 1026 3828 4.54 1082 4062 4.82 895 3596 4.27 955 3817 4.53 1013 4042 4.80 1068 4271 5.07 1121 4504 5.34 947 4073 4.83 1004 4294 5.09 1058 4518 5.36 1111 4747 5.63 1162 4978 5.91

999 4583 5.44 1053 4803 5.70 1105 5027 5.96 1155 5255 6.23 1204 5485 6.51 1052 5125 6.08 1103 5345 6.34 1152 5569 6.61 1200 5796 6.88 1247 6025 7.15 1105 5699 6.76 1153 5919 7.02 1200 6142 7.29 1246 6369 7.56 1291 6598 7.83 1158 6306 7.48 1204 6526 7.74 1249 6750 8.01 1293 6975 8.27 1336 7203 8.55

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

1069 3517 4.17 1125 3761 4.46 1180 4006 4.75 1232 4255 5.05 1283 4506 5.35 1102 3891 4.62 1156 4132 4.90 1208 4377 5.19 1259 4623 5.48 1308 4871 5.78 1136 4299 5.10 1188 4538 5.38 1239 4780 5.67 1288 5025 5.96 1335 5271 6.25 1173 4739 5.62 1223 4977 5.90 1272 5217 6.19 1319 5460 6.48 1365 5705 6.77 1211 5212 6.18 1259 5449 6.46 1306 5688 6.75 1352 5929 7.03 1396 6172 7.32 1251 5718 6.78 1297 5954 7.06 1342 6192 7.35 1386 6431 7.63 1429 6673 7.92 1292 6257 7.42 1337 6492 7.70 1380 6729 7.98 1423 6967 8.27 1464 7207 8.55 1335 6830 8.10 1377 7063 8.38 1419 7299 8.66 1460 7536 8.94 1501 7776 9.22 1378 7434 8.82 1419 7667 9.10 1460 7902 9.37 1499 8138 9.65 1538 8377 9.94

Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp Rpm Watts Bhp

1332 4750 5.65 1380 5015 5.95 1427 5272 6.25 1472 5531 6.56 1517 5793 6.87 1356 5122 6.08 1402 5375 6.38 1447 5630 6.68 1492 5886 6.98 1535 6144 7.29 1381 5519 6.55 1427 5770 6.84 1471 6022 7.14 1514 6276 7.45 ——— 1409 5951 7.06 1453 6199 7.35 1496 6449 7.65 1538 6701 7.95 ——— 1440 6417 7.61 1482 6663 7.90 1523 6911 8.20 —————— 1471 6916 8.20 1513 7161 8.49 ————————— 1505 7449 8.84 1545 7693 9.13 ————————— 1540 8016 9.51 ————————————

———————————————

LEGEND

Brake Horsepower Factory-Installed Option Input Watts to Motor

0.2 0.4 0.6 0.8 1.0

1.2 1.4 1.6 1.8 2.0

2.2 2.4 2.6 2.8 3.0

Fan Perform

Available External Static Pressure (in. wg)

ance — 551A240

2. Static pressure losses (i.e., EconoMi$er) must be added to external static pressure before entering Fan Performance table.

3. Interpolation is permissible. Do not extrapolate.

4. Fan performance is based on wet coils, clean filters, and casing losses. See Table 13 for accessory/FIOP static pressure information.

6. Use of a field-supplied motor may affect wiring size. Contact your Bryant representative for details.

—23—

Table 13 — Accessory/FIOP Static Pressure (in. wg)

UNIT 551A

155,180

240

LEGEND

FIOP —

NOTES:

1. Heaters are rated at 240 v, and 480 v.

2. The factory assembled horizontal adapter substantially improves

Factory-Installed Option

fan performance.

HEATER

RATED

VO LTAG E

208/240-3-60

480-3-60

208/240-3-60

480-3-60

CFM

3,750 0.05 (14/19, 26/34) 0.06 (42/56) 0.07 (56/75) 0.03 4,000 0.05 (14/19, 26/34) 0.06 (42/56) 0.07 (56/75) 0.04 5,000 0.07 (14/19, 26/34) 0.08 (42/56) 0.10 (56/75) 0.05 6,000 0.09 (14/19, 26/34) 0.12 (42/56) 0.15 (56/75) 0.07 7,200 0.11 (14/19, 26/34) 0.16 (42/56) 0.20 (56/75) 0.09 7,500 0.12 (14/19, 26/34) 0.17 (42/56) 0.21 (56/75) 0.10

3,750 0.05 (15, 32) 0.06 (55) 0.07 (80) 0.03 4,000 0.05 (15, 32) 0.06 (55) 0.07 (80) 0.04 5,000 0.07 (15, 32) 0.08 (55) 0.10 (80) 0.05 6,000 0.09 (15, 32) 0.12 (55) 0.15 (80) 0.07 7,200 0.11 (15, 32) 0.15 (55) 0.20 (80) 0.09 7,500 0.12 (15, 32) 0.17 (55) 0.21 (80) 0.10

5,000 0.08 (26/34) 0.11 (42/56) 0.14 (56/75) 0.06 6,000 0.09 (26/34) 0.12 (42/56) 0.15 (56/75) 0.07 7,200 0.11 (26/34) 0.16 (42/56) 0.20 (56/75) 0.09

9,000 0.15 (26/34) 0.19 (42/56) 0.24 (56/75) 0.11 10,000 0.17 (26/34) 0.21 (42/56) 0.26 (56/75) 0.12 11,250 0.20 (26/34) 0.24 (42/56) 0.29 (56/75) 0.14

5,000 0.08 (32) 0.11 (55) 0.14 (80) 0.06

6,000 0.09 (32) 0.12 (55) 0.15 (80) 0.07

7,200 0.11 (32) 0.15 (55) 0.20 (80) 0.09

9,000 0.15 (32) 0.19 (55) 0.24 (80) 0.11 10,000 0.17 (32) 0.21 (55) 0.26 (80) 0.12 11,250 0.20 (32) 0.24 (55) 0.29 (80) 0.14

ELECTRIC HEATERS

PRESSURE DROP

(kW)

3. The static pressure must be added to external static pressure. The sum and the evaporator entering-air cfm should then be used in conjunction with the Fan Performance table to determine blower rpm, bhp, and watts.

ECONOMI$ER

PRESSURE

DROP

Fig. 29 — Perfect Humidity™ Operation Diagram

—24—

Table 14 — Perfect Humidity™ Dehumidification

Package Static Pressure Drop (in. wg)

UNIT SIZE

551A

155 180 240

UNIT NOMINAL

TONS

12 .026 .045 .071 15 .040 .071 .111 20 .071 .126 .197

Table 15 — Fan RPM at Motor Pulley Settings*

551A 0 0.5 1 1 155† 155** 180† 180** 240† 240**

†† †† †† †† 1064 1035 1006 978 949 920 891 863 834 †† †† †† †† 1426 1393 1360 1327 1294 1261 1227 1194 1161 †† †† †† †† 1021 1002 984 965 947 928 910 891 873 †† †† †† †† 1200 1178 1156 1134 1112 1091 1069 1047 1025 †† †† †† †† 1151 1132 1114 1095 1077 1058 1040 1021 1002 †† †† †† †† 1369 1347 1325 1303 1281 1259 1237 1215 1193

*Approximate fan rpm shown.

†Indicates standard drive package.

**Indicates alternate drive package.

††Due to belt and pulley style, pulley cannot be set to this number of turns open.

CFM PER TON

300 400 500

BHP —

UNIT 551A

155

(Standard

Motor)

155

(Optional

Motor)

180

240

LEGEND

Brake Horsepower

Table 16 — Evaporator Fan Motor Specifications

NOMINAL

VOLTAGE

2.9 208 2700 85.8 3.13 2.34 9.46

2.9 230 2700 85.8 3.13 2.34 8.6

2.9 460 2700 85.8 3.13 2.34 4.3

3.7 208 3775 85.8 4.38 3.27 10.5

3.7 230 3775 85.8 4.38 3.27 10.5

3.7 460 3775 85.8 4.38 3.27 4.8 5 208 5180 87.5 6.13 4.57 15.8

5 230 5180 87.5 6.13 4.57 15.8 5 460 5180 87.5 6.13 4.57 7.9

7.5 208 7915 88.5 9.47 7.06 22

7.5 230 8640 88.5 10.33 7.71 22

7.5 460 8640 88.5 10.33 7.71 13

MAX

WATTS

EFF.

MAX BHP

MAX BkW

MAX

AMPS

—25—

SERVICE

WARNING:

Before performing service or maintenance operations on unit, turn off main power switch to unit and install lockout tag on disconnect switch. Turn off accessory heater power switch if applicable. Electrical shock could cause personal injury.

I. CLEANING

Inspect unit interior at beginning of each heating and cooling season and as operating conditions require. Remove unit top panel and/or side panels for access to unit interior.

A. Evaporator Coil

Clean as required with a commercial coil cleaner.

B. Condenser Coil

Clean condenser coil annually and as required by location and outdoor-air conditions. Inspect coil monthly — clean as required.

C. Condensate Drain

Check and clean each year at start of cooling season. In winter, keep drains and trap dry.

D. Filters

Clean or replace at start of each heating and cooling season, or more often if opera ting c ondit ions re quire. Refer to T able 1 for type and size.

E. Outdoor-Air Inlet Screens

Clean screens with steam or hot water and a mild detergent. Do not use throwaway filters in place of screens.

II. LUBRICATION

A. Compressors

Each compressor is charged with the correct amount of oil at the factory. Conventional white o il (Sontext 200LT) is used. White oil is compatible with 3GS oil, and 3GS oil may be used if the additi on of oil is requi red. See c ompressor n ameplate for original oi l charge. A complete recharge should be four ounces less than the original oil charge. When a compressor is exchanged in the field it is possible that a major portion of the oil from the repl aced compresso r may still be in the system. While this will not affect the reliability of the replacement compressor, the extra oil will add rotor drag and increase power usa ge. To remove this excess o il, an access valve may be added to the lower portion of the suction line at the inlet of the compressor. The compressor should then be run for 10 minutes, shut down, and the access valve opened until no oil flows. This should be repeated twice to make sure the proper oil le vel has been achieved.

B. Fan Shaft Bearings

For size 155 units, bearings are permanently lubricated. No field lubrication is required. For size 180 and 240 units, the bearings are of the pillow block type and have grease fittings. The bearing opposite the motor end has an extended tube line so it can be lubrica ted from the motor side. Lubri cate the bearings twice annually.

Typical lubricants are given below:

MANUFACTURER LUBRICANT

Texaco

Mobil

Sunoco

Texaco

*Preferred lubricant because it contains rust and oxidation inhibitors.

Regal AFB-2*

Mobilplex EP No. 1

Prestige 42

Multifak 2

C. Condenser and Evaporator-Fan Motor Bearings

The condenser and ev ap orat or-fan motor s have pe rman en tly sealed bearings, so no field lubrication is necessary.

III. EVAPORATOR FAN PERFORMANCE ADJUSTMENT (Fig. 30-32)

Fan motor pulleys are factory set for speed shown in Table 1. To change fan speeds:

1. Shut off unit power supply.

2. a. Size 155 Only: Loosen belt by loosening fan motor mounting plate nuts.

b. Size 180 and 240 Only: Loosen nuts on the 2 car-

riage bolts in the motor mounting base. Install jacking bolt and plate under motor base (bolt and plate are shipped in installer’s packet). See F ig. 32. Using bolt and plate, raise motor to top of slide and remove belt. Secure motor in this position by tightening the nuts on the carriage bolts.

3. Loosen movable-pulley flange setscrew (see Fig. 30).

4. Screw movable flange toward fixed flange to increase

speed and away from fixed flange to decrease speed. Increasing fan speed increases load on motor. Do not exceed maximum speed specified in Table 1.

See Table 8 for air quantity limits.

5. Set movable flange at nearest keyway of pulley hub

and tighten setsc rew. (See Table 1 for speed change for each full turn of pulley flange.)

6. Replace and tighten belts. See Belt Tension Adjust-

ment section on page 27.

To align fan and motor pulleys:

1. Loosen fan pulley setscrews.

2. Slide fan pulley along fan shaft.

3. Make angular alignment by loosening motor from

mounting plate.

IV. EVAPORATOR FAN SERVICE AND REPLACEMENT

A. 551A155 Units (See Fig. 31)

NOTE: To remove belts only, follow Steps 1-6.

1. Remove filter and supply-air section panels.

2. Remove unit top panel.

3. Loosen carriage nuts A and B holdin g motor mount

assembly to fan scroll side plates.

4. Loosen sc re w C.

5. Rotate motor mount assembly (with motor attached)

as far as possible away from evaporator coil.

6. Remove belt.

7. Rotate motor mount assembly back past original

position toward evaporator coil.

8. Remove motor mounting nuts D and E (both sides).

9. Lift motor up through top of unit.

10. Reverse above procedure to reinstall motor.

11. Check and adjust belt tension as necessary.

B. 551A180,240 Units (See Fig. 32)

The 551A180,240 units use a fan motor mounting system that features a slide-out motor mounting plate. To replace or service the motor, slide out the bracket.

1. Remove the evaporator-fan access panel and the

heating control access panel.

2. Remove the center post (located betwe en the ev apor a-

tor fan and heating control access panels) and all screws securing it.

—26—

Fig. 30 — Evaporator-Fan Pulley Alignment

and Adjustment

3. Loosen nuts on the two carriage bolts in the motor

mounting base.

4. Using jacking bolt under motor base, raise motor to

top of slide and remove belt. Secure motor in this position by tightening the nuts on the carriage bolts.

5. Remove the belt drive.

6. Remove jacking bolt and tapped jacking bolt plate.

7. Remov e the 2 screws that secure the motor mounti ng

plate to the motor support channel.

8. Remove the 3 screws from the end of the motor sup-

port channel that interfere with the motor slide path.

9. Slide out the motor and motor mounting plate.

10. Disconnect wiring connections and remove the 4 mounting bolts.

11. Remove the motor.

12. To install the new motor, reverse Steps 1-11.

Fig. 31 — 551A155 Evaporator-Fan

Motor Section

NOTE:

packet. They should be added to the motor support channel below the motor mounting plate to aid in raising the motor. The plate part number is 50DP503842. The adjustment bolt is

A 3

/2-in. bolt and threaded plate are included in the installer’s

/8- 16 x 21/2 LG.

Fig. 32 — 551A180,240 Evaporator-Fan

Motor Section

V. BELT TENSION ADJUSTMENT

To adjust belt tension:

1. Loosen fan motor bolts.

2. Adjust belt tension: a. Size 155 Units: Move m oto r mo unt in g pla te up or

down for proper belt tension (

/2 in. deflection

with one finger).

b. Size 180, 240 Units: Turn motor jacking bolt to

move motor mounting plate up or down for proper belt tension (

/8 in. deflection at midspan

with one finger [9 lb force]).

3. Tighten nuts.

4. Adjust bolts and nut on mounting plate to secure

motor in fixed position.

—27—

VI. CONDENSER-FAN ADJUSTMENT

A. 551A155 and 180 Units (Fig. 33)

1. Shut off unit power supply.

2. Remove access panel(s) closest to the fan to be adjusted.

3. Loosen fan hub setscrews .

4. Adjust fan height on shaft using a straightedge placed across the fan orifice.

5. Tighten setscrews and replace panel(s).

6. Turn on unit power.

B. 551A240 Units (Fig. 34)

1. Shut off unit power supply.

2. Remove fan top-grille assembly and loosen fan hub screws.

3. Adjust fan height on unit, using a straightedge placed across the fan orifice.

4. Tighten setscrews and replace rubber hubcap to prevent hub from rusting to motor shaft.

5. Fill hub recess with permagum if rubber hubcap is missing.

NOTE: Dimensions are in inches).

Fig. 33 — Condenser-Fan Adjustment,

551A155,180

NOTE: Dimensions are in inches.

Fig. 34 — Condenser-Fan Adjustment,

551A240

VII. ECONOMI$ER ADJUSTMENT

A. LED Indication

The EconoMi$er controller features an onboard diagnostic LED (light-emitting diode) that flashes to indicate its status. See Table 17 for flash codes. The controller also has terminal connections (REM LED) for remotely mounting an LED, if desired. The flash code priorities are as follows:

1. On/Off or continuous flash

2. Critical fault

3. Non-critical fault

If any sensors are opened, shorted, or removed, the EconoMi$er determines whether the failure is critical or non-critical and flashes the appropriate code . If a non-critical sensor fault occurs (i.e., outdoor air humidity), the EconoMi$er automatically reconfigures its control strategy to a more appropriate m ode. If a critical sensor fault occurs (i.e., supply air sensor), the EconoMi$er reverts to a safe mode of operation until the sensor problem is resolved.

B. Manual Configuration Pushbutton

The EconoMi$er cont roller also featur es an onboard button (CONFIG) to help troub leshoot the sy stem. See Fig. 16. The button can perform 3 different functions.

Pressing the CONFIG button for more than three seconds, but less than ten seconds and then releasing will start the automatic test procedure. The damper will modulate fully open, wait, and modulate closed. This process takes three minutes to complete. Use this feature to determine if the actuator can be commanded.

If the CONFIG button is pressed and held for ten seconds and less than 30 seconds then released, th e EconoMi$er controller reconfigures its mode of operation based on the sensors that are connected and functioning normally, and cancels the automatic test procedure.

If the EconoMi$er co ntrol ler reco gni zed a non- cr itica l se nso r fault, and flashed a code (i.e., FLASH 6, outdoor air humidity sensor fault) the FLASH CODE will be cleared, and normal operation begins. Ensure faulty sensor is removed before clearing faults.

If the EconoMi$er controller recognizes a critical sensor fault, and flashes a code (i.e., FLASH 4, discharge air thermostat fault) the FLASH code will not be cleared, and the EconoMi$er will remain in the safe operation mode. The sensor fault must be corrected to enable EconoMi$er to revert to normal operation.

Table 17 — EconoMi$er Control Module Flash Code Identification

FLASH CODE CAUSE ACTION TAKEN BY ECONOMI$ER

Constant On Constant Off Continuous

Flash Flash One Flash Two Flash Three

Flash Four

Critical Fault

Flash Five

Flash Six

Flash Seven

Flash Eight

Flash Nine

Non-Critical Fault

Flash Ten

Normal operation Normal operation. No power No operation. CONFIG button pushed and held

between 3 and 9 seconds Control board fault System shutdown. Thermostat fault (i.e., Y2 without Y1) System shutdown until corrected. Actuator fault Revert to mechanical cooling only.

Discharge air thermistor fault

Outdoor air temperature sensor fault

Outdoor air humidity sensor fault Continue operation with dry bulb or dry bulb differential switchover.

Return air temperature sensor fault

Return air humidity sensor fault

Carbon Dioxide (CO

Onboard adjustment potentiometer fault Continue operation with default potentiometer settings.

) sensor fault Continue operation without ventilation control.

Outdoor air damper is stroked fully open, then closed (automatic test procedure takes 3 minutes to complete).

Continue operation with damper at minimum position. Revert to mechanical cooling only.

Continue operation with damper at minimum position. Disable mechanical cooling lockout.

Continue operation with single enthalpy EconoMi$er switchover or dry bulb EconoMi$er switchover (without humidity sensor).

Continue operation with single enthalpy, differential dry bulb, or dry bulb EconoMi$er switchover.

—28—

If the CONFIG button is pressed and held for more than 30 seconds and released, the EconoMi$er controller will enable the enthalpy comparison strategy (with outdoor air enthalpy and return air enthalpy sensors installed).

VIII. POWER FAILURE

Dampers have a spring return. In event of power failure, dampers will return to fully closed position until power is restored. Do not manually operate damper motor.

IX. REFRIGERANT CHARGE

Amount of refrigerant charge is listed on unit nameplate and in Table 1. Refer to Carrier GTAC II; Module 5; Charging, Recovery, Recycling, and Reclamation section for charging methods and procedures. Unit panels must be in place when unit is operating during charging procedure.

NOTE: Do not use recycled refrigerant as it may contain contaminants.

A. No Charge

Use standard evacuating techniques. After evacuating system, weigh in the specified amount of re frigerant (refer to Table 1).

B. Low Charge Cooling

Using cooling charging chart (see Fig. 35), add or remove refrigerant until conditions of the chart are m et. Note that charging chart is different from those normally used. An accurate pressure gage and temperature-sensing device is required. Chargi ng is accomplished by ens uring the proper amount of liquid subcooling. Measure liquid line pressure at the liquid line service valve using pressure gage. Connect temperature sensing device to the liquid line near the liquid line service valve and insulate it so that outdoor ambient temperature does not affect reading.

C. To Use The Cooling Charging Chart

Use the above temperature and pressure readings, and find the intersection point on the cooling charging chart. If intersection point on chart is a bove line, add refrige rant. If intersection point on chart is below line, carefully recover some of the charge. Recheck suction pressure as charge is adjusted.

BOTH CIRCUITS

REDUCE CHARGE IF BELOW CURVE

150

200

250

300

350

400

140

120

100

LIQUID TEMPERATURE AT LIQUID VALVE (DEG F)

ALL OUTDOOR FANS MUST BE OPERATING

ADD CHARGE IF ABOVE CURVE

100

LIQUID PRESSURE AT LIQUID VALVE (PSIG)

Fig. 35 — Cooling Charging Chart

NOTE: Indoor-air CFM must be within normal operating

range of unit. All o utdoor fans must be operating. The TXV (thermostatic expansion valve) is set to main-

tain between 15 and 20 degrees of superheat at the compressors. The valves are factory set and should not require re-adjustment.

D. Perfect Humidity™ System Charging

The system charge for units with the Perfect Humidity option is greater than that of the standard unit alone. The charge for units with this option is indicated on the unit nameplate drawing. To charge systems using the Perfect Humidity Dehumidification package, fully evacuate, recover, and re-charge the system t o the namepla te specifie d charge level. To check or adjust refrige rant charge on systems using the Perfect Humidity Dehumidification package, charge per the standard subcooling charts. The subcooler MUST be deenergized to use the charging charts. The charts reference a liquid pressure (psig) and temperature at a point between the condenser coil and the s ubcooler coil. A tap is provided on the unit to measure liquid pressure entering the subcooler (leaving t he condenser).

X. FILTER DRIER

Replace whenever refrigerant system is exposed to atmosphere.

XI. PROTECTIVE DEVICES

A. Compressor Protection

Overtemperature Each compressor has an internal protector to protect it

against excessively high discharge gas temperatures. Overcurrent Each compressor has internal line break motor protection. Crankcase Heater All units are equipped with a 70-watt crankcase hea ter to

prevent absorptio n of liquid refrigera nt by oil in the crankcase when the compressor is idle. The crankcase heater is energized whenev er there is a main power to the unit and the compressor is not energized.

IMPORTANT: After prolonged shutdown or servicing, energize the crankcase heaters for 24 hours before starting the compressors.

Compressor Lockout If any of the safeties (high-pressure, low-pressure, freeze

protection thermostat, compressor internal thermostat) trip, or if there is loss of power to the compressors, the C LO (compressor lockout) will lock th e comp ressors o ff. To reset, manually move the thermostat setting.

B. Evaporator Fan Motor Protection

A manual reset, calibrated trip, magnetic circuit breaker protects against ov ercurrent. Do not bypass connections or increase the size of the breaker to correct troubl e. Determine the cause and correct it before r esetting the breaker.

C. Condenser-Fan Motor Protection

Each condenser-fan motor is internally protected against overtemperature.

D. High- and Low-Pressure Switches

If either switch trips, or if the compressor overtemperature switch activates, that refrigerant circuit will be automatically locked out by the CLO. To reset, manually move the thermostat setting.

—29—

E. Freeze Protection Thermostat (FPT)

An FPT is located on the top and bottom of the evaporator coil. It detects frost build-up and turns off the compressor, allowing the coil to clear. Once the frost has melted, the compressor can be reenergized.

XII. RELIEF DEVICES

All units have relief devices to protect against damage from excessive pressures (e.g ., fire). These devices protect the high and low side.

XIII. CONTROL CIRCUIT, 24-V

This control circuit is protected against overcurrent by a

3.2-amp circuit breaker. Breaker can be reset. If it trips, determine cause of trouble before resetting. See Fig. 36 and

37.

XIV. REPLACEMENT PARTS

A complete list of replacement parts may be obtained from any Bryant distributor upon reque st.

XV. ECONOMI$ER LEDs

The EconoMi$er control module has LEDs for diagnostic purposes. The flash code identification is shown in Table 17.

LEGEND AND NOTES FOR FIG. 36 AND 37

AHA — BRK W/AT — C — CAP — CB — CC — CH — CLO — COMP — CR — DAT — DM — DU — EC — EQUIP — FL — FPT — FU — GND —

Adjustable Heat Anticipator Breaks with Amp Turns Contactor, Compressor Capacitor Circuit Breaker Cooling Compensator Crankcase Heater Compressor Lockout Compressor Motor Control Relay Discharge Air Thermistor Damper Motor Dummy Terminal Enthalpy Control Equipment Fuse Link Freeze Protection Thermostat Fuse Ground

HC — HPS — HTR — IFC — IFCB — IFM — IFR — L — LPS — LS — NEC — OAT — OFC — OFM — OP — PL — PRI — QT — SW —

Heater Contactor High-Pressure Switch Heater Indoor-Fan Contactor Indoor-Fan Circuit Breaker Indoor-Fan Motor Indoor-Fan Relay Light Low-Pressure Switch Limit Switch National Electrical Code Outdoor-Air Thermostat Outdoor-Fan Contactor Outdoor-Fan Motor Overcurrent Protection Plug Assembly Primary Quadruple Terminal Switch

XVI. OPTIONAL HINGED ACCESS DOORS

When the optional serv ice package is ordered or the if the hinged access d oors option is ordered, the u nit will be provided with external and internal hinged access doors to facilitate service.

Four external hinged access door s are pro vided. All extern al doors are provided with 2 large

/4 turn latches with folding bail-type handles. (Compressor access doors have one latch.) A single door is provided for filter and drive access. One door is provided for control box access. The control box access door is interlocked with the non-fused disconnect which must be in the OFF position to open the door. Two doors are provided for access to the compressor compartment.

Two internal access doors are provided in side the filter/drive access door. The filter access door (on the left) is secured by 2

small

/4 turn latches with folding bail-type handles. This door must be opened prior to opening the drive access door. The drive access door is shipped with 2 sheet metal screws holding the door closed. Upon initial opening of the door, these screws may be removed and discarded. The door is then held shut by the filter access door, which closes over it.

LEGEND

TB — TC — TH — TRAN —

Terminal Block Thermostat Cooling Thermostat Heating Transformer

Terminal (Marked)

Terminal (Unmarked)

Terminal Block

Splice

Factory Wiring Field Wiring Option/Accessory Wiring To indicate common potential

only; not to represent wiring.

NOTES:

1. Compressor and/or fan motor(s) thermally protected; 3-phase motors protected against primary single-phasing conditions.

2. If any of the original wire furnished must be replaced, it must be replaced with type 90° C wire or its equivalent.

3. Jumpers are omitted when unit is equipped with EconoMi$er.

5. IFCB must trip amps is equal to or less than 140% FLA.

6. The CLO locks out the compressor to prevent short cycling on compressor overload and safety devices. Before replacing CLO, check these devices.

7. Number(s) indicates the line location of used contacts. A bracket over (2) numbers signifies a single-pole, double-throw contact. An underlined number signifies a normally closed contact. Plain (no line) number signifies a normally open contact.

—30—

Fig. 36 — Typical Wiring Schematic (551A180, 460v Shown)

—31—

Fig. 36 — Typical Wiring Schematic (551A180, 460v Shown) (cont)

Fig. 37 — Typical Component Arrangement (551A180 Shown)

—32—

PROBLEM CAUSE REMEDY

Compressor and condenser fan will not start.

Compressor will not start but condenser fan runs.

Compressor cycles (other than normally satisfying thermostat).

Compressor operates continuously.

Excessive head pressure.

Head pressure too low.

Excessive suction pressure.

Suction pressure too low.

TXV —

Thermostatic Expansion Valve

LEGEND

TROUBLESHOOTING

Refer to Tables 18-20 for troubleshooting details.

Table 18 — Cooling Service Analysis

Power failure. Call power company. Fuse blown or circuit breaker tripped. Replace fuse or reset circuit breaker. Defective thermostat, contactor, transformer, or control

relay. Insufficient line voltage. Determine cause and correct. Incorrect or faulty wiring. Check wiring diagram and rewire correctly. Thermostat setting too high. Lower thermostat setting below room temperature. Faulty wiring or loose connections in compressor circuit. Check wiring and repair or replace. Compressor motor burned out, seized, or internal

overload open. Defective overload. Determine cause and replace. Compressor locked out Determine cause for safety trip and reset lockout. One leg of 3-phase power dead. Replace fuse or reset circuit breaker.

Refrigerant overcharge or undercharge. Recover refrigerant, evacuate system, and recharge

Defective compressor. Replace and determine cause. Insufficient line voltage. Determine cause and correct. Blocked condenser. Determine cause and correct. Defective overload. Determine cause and replace. Defective thermostat. Replace thermostat. Faulty condenser-fan motor. Replace. Restriction in refrigerant system. Locate restriction and remove. Dirty air filter. Replace filter. Unit undersized for load. Decrease load or increase unit size. Thermostat set too low. Reset thermostat. Low refrigerant charge. Locate leak, repair, and recharge. Air in system. Recover refrigerant, evacuate system, and recharge. Condenser coil dirty or restricted. Clean coil or remove restriction. Dirty air filter. Replace filter. Dirty condenser coil. Clean coil. Refrigerant overcharged. Recover excess refrigerant. Faulty TXV. 1. Check TXV bulb mounting and secure tightly to

Air in system. Recover refrigerant, evacuate system, and recharge. Condenser air restricted or air shor t-cycling. Determine cause and correct. Low refrigerant charge. Check for leaks, repair, and recharge. Restriction in liquid tube. Remove restriction. High heat load. Check for source and eliminate. Faulty TXV. 1. Check TXV bulb mounting and secure tightly to

Refrigerant overcharged. Recover excess refrigerant. Dirty air filter. Replace filter. Low refrigerant charge. Check for leaks, repair, and recharge. Metering device or low side restricted. Remove source of restriction. Faulty TXV. 1. Check TXV bulb mounting and secure tightly to

Insufficient evaporator airflow. Increase air quantity. Check filter and replace if

Temperature too low in conditioned area. Reset thermostat. Field-installed filter drier restricted. Replace.

Replace component.

Determine cause. Replace compressor.

Determine cause.

to nameplate.

suction line.

2. Replace TXV if stuck open or closed.

suction line.

2. Replace TXV if stuck open or closed.

suction line.

2. Replace TXV if stuck open or closed.

necessary.

—33—

Table 19 — EconoMi$er Troubleshooting

PROBLEM POTENTIAL CAUSE REMEDY

Damper Does Not Open

EconoMi$er Operation Limited to Minimum Position

Damper Position Less than Minimum Position Set Point

Damper Does Not Return to Minimum Position

Damper Does Not Close on Power Loss

LEGEND

IFM — PL —

Indoor Fan Motor Plug

Indoor (Evaporator) Fan is Off

Check to ensure that 24 vac is present at Terminal C1 (Common Power) on the IFC (Indoor [Evaporator] Fan Contactor) or that 24 vac is present at the IFO (Indoor [Evaporator] Fan On) terminal. Check whether 24 vac is present at PL6-1 (red wire) and/or PL6-3 (black wire). If 24 vac is not present, check wiring (see unit label diagram).

Check proper thermostat connection to G on the connection board.

No Power to EconoMi$er Controller

Check to ensure that 24 vac is present across Terminals 24 VAC and 24 V COM on the EconoMi$er control. If 24 vac is not present, check wiring (see unit label diagram). If 24 vac is present, STATUS light should be on constantly.

No Power to G Terminal If IFM is on, check to ensure 24 vac is present on G Terminal of the

EconoMi$er controller. If 24 vac is not present, check wiring (see unit label diagram).

Controller Fault If STATUS light is flashing one flash, the EconoMi$er controller is

experiencing a fault condition. Cycle power to the controller. If condition continues, replace the EconoMi$er controller.

Thermostat Fault If STATUS light is flashing two flashes, the EconoMi$er controller senses that

the thermostat is wired incorrectly. Check wiring between the thermostat and the connection board in the electrical panel. The fault condition is caused by Y2 being energized before Y1.

Actuator Fault Check the wiring between the EconoMi$er controller and the actuator.

Hold CONFIG button between 3 and 10 seconds to verify the actuator’s operation. (This process takes 3 minutes to complete.)

Minimum Position Set Incorrectly

EconoMi$er Changeover Set Point Set Too High or

Verify that the MIN POS (%) is set greater than zero. Adjust MIN POS (%) to 100% to verify operation, and then set to correct setting.

Set at correct value. See Table 6.

Too Low Discharge Air

Thermistor Faulty Outdoor Air Temperature

Sensor Faulty Supply Air Low Limit

Strategy Controlling

If STATUS light is flashing 4 flashes, Discharge Air Thermistor is faulty. Check wiring or replace sensor.

If STATUS light is flashing 5 flashes, Outdoor Air Temperature Sensor is faulty. Check wiring or replace sensor.

The supply-air temperature is less than 45 F, causing the minimum position to be decreased. Refer to the Start-Up instructions. Verify correct setting of MIN POS (%). If correct, EconoMi$er is operating correctly.

Ventilation Strategy

Controlling

Damper Travel is Restricted

If a CO2 sensor is being used, and the damper position is greater than minimum position, the ventilation control strategy is controlling. Refer to the Start-Up instructions. EconoMi$er is operating correctly.

Check to ensure the damper is not blocked.

Table 20 — Perfect Humidity™ Dehumidification Subcooler Service Analysis

PROBLEM CAUSE REMEDY

Subcooler will not energize

Subcooler will not deenergize

Low system capacity

No power to subcooler control transformer.

No power from subcooler control transformer to liquid line three way valve.

Liquid line three-way valve will not operate.

Liquid Line three-way valve will not close.

Low refrigerant charge or frosted coil.

Check power source. Ensure all wire connections are tight.

1. Fuse open; check fuse. Ensure continuity of wiring.

2. Subcooler control low-pressure switch open. Cycle unit off and allow low-pressure switch to reset. Replace switch if it will not close.

3. Transformer bad; check transformer.

1. Solenoid coil defective; replace.

2. Solenoid valve stuck closed; replace.

Valve is stuck open; replace.

1. Check charge amount. See system charging section.

2. Evaporator coil frosted; check and replace subcooler control low pressure switch if necessary.

START-UP CHECKLIST

MODEL NO.:

SERIAL NO.:

DATE: TECHNICIAN:

I. PRE-START-UP:



VERIFY THAT ALL PACKING MATERIALS HAVE BEEN REMOVED FROM UNIT



VERIFY INSTALLATION OF INDOOR FAN MOTOR ADJUSTMENT BOLT (155 UNITS) OR ADJUSTMENT BOLT AND PLATE (180, 240 UNITS)



VERIFY INSTALLATION OF OUTDOOR AIR HOOD



VERIFY THAT CONDENSATE CONNECTION IS INSTALLED PER INSTRUCTIONS



VERIFY THAT ALL ELECTRICAL CONNECTIONS AND TERMINALS ARE TIGHT



CHECK THAT FILTERS AND SCREENS ARE CLEAN AND IN PLACE



VERIFY THAT UNIT IS LEVEL



CHECK FAN WHEEL AND PROPELLER FOR LOCATION IN HOUSING/ORIFICE, AND VERIFY SETSCREW IS TIGHT



VERIFY THAT FAN SHEAVES ARE ALIGNED AND BELTS ARE PROPERLY TENSIONED



VERIFY THAT SCROLL COMPRESSORS ARE ROTATING IN THE CORRECT DIRECTION



VERIFY THAT CRANKCASE HEATER HAS BEEN ENERGIZED FOR 24 HOURS

II. START-UP:

ELECTRICAL

SUPPLY VOLTAGE L1-L2 L2-L3 L3-L1 COMPRESSOR AMPS — COMPRESSOR NO. 1 L1 L2 L3 — COMPRESSOR NO. 2 L1 L2 L3 SUPPLY F AN AMPS

EXHAUST FAN AMPS

CUT ALONG DOTTED LINE

ELECTRIC HEAT AMPS (IF SO EQUIPPED) L1 L2 L31

TEMPERATURES

OUTDOOR-AIR TEMPERATURE RETURN-AIR TEMPERATURE COOLING SUPPLY AIR ELECTRIC HEAT SUPPLY AIR (IF SO EQUIPPED)

F DB (Dry-Bulb) F DB F WB (Wet-Bulb) F

PRESSURES

REFRIGERANT SUCTION CIRCUIT NO. 1 PSIG CIRCUIT NO. 2 PSIG REFRIGERANT DISCHARGE CIRCUIT NO. 1



VERIFY REFRIGERANT CHARGE USING CHARGING CHART ON PAGE 29.

PSIG CIRCUIT NO. 2 PSIG

GENERAL



ECONOMI$ER MINIMUM VENT AND CHANGEOVER SETTINGS TO JOB REQUIREMENTS



VERIFY INSTALLATION OF ALL OPTIONS AND ACCESSORIES

CUT ALONG DOTTED LINE

CL-1

CATALOG NO. 5355-105

Bryant Durapac Plus 551a User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual