Bryant 542J User Manual

installation, start-up and
service instructions

SINGLE PACKA GE ROOFT OP
HEAT PUM P UNITS

Cancels: II 542J-150-3 II 542J-150-4

Dura

Pac

542J

Plus Series

Sizes 150,180

12 and 15 Tons

3/15/06

CONTENTS

Page

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

INSTALLATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-18

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

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

III. Step 3 — Field Fabricate Ductwork . . . . . . . . . . . . . 1

IV. Step 4 — Make Unit Duct Connections . . . . . . . . . . 3

V. Step 5 — Trap Condensate Drain. . . . . . . . . . . . . . . 3

VI. Step 6 — Make Electrical Connections . . . . . . . . . . 7

VII. Step 7 — Make Outdoor-Air Inlet Adjustments. . . 10

VIII. Step 8 — Install Outdoor-Air Hood. . . . . . . . . . . . . 10

IX. Step 9 — Install All Accessories . . . . . . . . . . . . . . 10

X. Step 10 — Adjust Factory-Installed Options. . . . . 11

XI. Step 11 — Defrost Cycle . . . . . . . . . . . . . . . . . . . . . 18

START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18-22

SERVICE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23-29

TROUBLESHOOTING. . . . . . . . . . . . . . . . . . . . . . . . . . . .30-35

INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

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, repair, or service air-conditioning equipment.

Untrained personnel can perform basic maintenance func­tions of cleaning coils and filters and replacing filters. All
other operations should be performed by trained se rvice per­sonnel. When working on air-conditioning equipment, observe
precautions in the literature, tags and labels attached to the
unit, and other safety pre c au ti ons th at ma y a ppl y.

Follow all safety codes. Wear safety glasses and work gloves.
Use quenching cloth for unbrazing operations. Have fire
extinguisher available for all brazing operations.

WARNING: Before performing service or mainte­nance operations on unit, turn off main power switch to
unit. Electrical shock could cause personal injury.

INSTALLATION

IMPORTANT: Units have high ambient operating limits. If

limits are exceeded , the un it will au tomatica lly lock the com­pressor out of operation. Manual reset will be required to
restart the compressor.

I. STEP 1 — PROVIDE UNIT SUPPORT
A. Roof Curb

Assemble and install a ccessory roof curb in accordanc e with
instructions shipped with the curb. Accessory roof curb and
information required to field fabricate a roof curb are shown

in Fig. 1 and 2. Install insulation, cant strips, roofing, and
counter flashing as shown. Du ctwork can be secured to roof
curb before unit is set in pl ace. Horizontal adapter installa­tion is shown in Fig. 2.

IMPORTANT: Th e gasketing of the unit to the roof curb is crit­ical for watert ight seal. Install ga sket suppli ed with the ro of
curb as shown in Fig. 1. Improp erly applied gasket can result
in air leaks and poor unit performance.

Curb should be level. This is necessary to permit unit drain to
function properly. Unit leveling tolerances is ±
ear ft in any dire ction . Refe r to Accessory Roof Curb Installa­tion Instructions for addition al information as required.

B. Alternate Unit Support

When the curb cannot be used, support unit with sleepers
using unit curb support area. If sleepers cannot be used, sup­port long sides of 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 damage. File any claim with
transportation agency. Keep unit upright, and do not drop.
Use spreader bars over unit to prevent sl ing or cabl e damage.
Rollers may be used to move unit across a roof. Level by using
unit frame as a reference; leveling tolerance is ±
linear ft in any direction. See Fig. 1 for additional leveling tol­erance 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 inst ructions 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.

III. STEP 3 — FIELD FABRICATE DUCTWORK

Secure all ducts to buildi ng structure. Use flexible duct con­nectors between unit and ducts as required. Insulate and
weatherproof all external ductwo rk, join ts, and roof openings
with counter flashing and mastic in accordanc e with applica­ble codes.

Ducts passing through an unconditioned space must be insu­lated and covered with a vapor barrier.

The 542J units with electric heat requi r e a 1-in. clearance for
the first 24 in. of ductwork.

1

/16 in. per lin-

1

/

in. per

16

lb density.

2

/

1

AB

Deg. in. Deg. in.

DIMENSIONS (degrees and inches)*

ALL .28 .45 .28 .43

UNIT

below the unit discharge for units equipped with electric heaters.

1. Roof curb accessory is shipped disassembled.

2. Insulated panels: 1″ thick neoprene coated 1

3. Dimensions in ( ) are in millimeters.

NOTES:

4. Direction of airflow.

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

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

6. A 90 degree elbow must be installed on the supply ductwork

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

DESCRIPTION

CURB

HEIGHT

Fig. 1 — Roof Curb Details

Standard Curbfor Units

Requiring High Installation

Side Supply and Return

Curb for High Installation

PKG. NO. REF.

CRRFCURB010A00 1′-2″ (305) Standard Curb 14″ High

CRRFCURB011A00 2′-0″ (610)

CRRFCURB012A00 2′-0″ (610)

—2—

3 1/2"

2" X 1/4
SUPPORT TYP.
STITCH WELDED

FULLY INSULATED
SUPPLY PLENUM
1" INSULATION
1 1/2 # DENSITY,
STICK PINNED & GLUED

NOTE: CRRFCURB013A00 is a fully factory preassembled horizontal
adapter and includes an insulated transition duct. The pressure drop
through the adapter curb is negligible.

For horizontal return applications: The power exhaust and barometric

relief dampers must be installed in the return air duct.

Fig. 2 — Horizontal Supply/Return Adapter Installation

MAXIMUM

UNIT 542J

150 1895 860 3-1 948
180 2205 1000 3-6 1059

NOTES:

1. Dimensions in ( ) are in millimeters.

2. Refer to Table 1 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$erIV. See Table 1 for
EconoMi$erIV weight.

6. Weights given are for aluminum indoor coil plate fins and copper
outdoor coil plate fins. Weights of other metal combinations are
listed in Table 1.

SHIPPING WEIGHT

lb kg ft-in. mm

DIMENSION A

CAUTION: All panels must be in place when rigging.

Fig. 3 — Rigging Details

14 3/4"

6"

ACCESSORY

PACKAGE NO.

CRRFCURB013A00

12" WIDE STANDING
SEAM PANELS

CURB

HEIGHT

1′-11″

(584)

DESCRIPTION

Pre-Assembled, Horizontal

Adapter Roof Curb

23"

Outlet grilles must not lie directly below unit discharge.
NOTE: A 90-degree elbo w must be provid ed in the du ctwork

to comply with UL (Underwriters Laboratori es ) co d e s f or use
with electric heat.

WARNING: For vertical supply and return units,
tools or parts could drop into ductwork and cause an
injury. Insta ll a 90-de gree t urn in th e return ductwor k
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 connections. Duct­work openings are shown in Fig. 6. Field-fabricated concen­tric ductwork may be connected as shown in 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 or 5 and 9 for drain location. Plug is provided in
drain hole and must be removed when unit is operating. One

3

/4-in. half coupling is provided inside unit indoor air section
for condensate drain connection. An 81/2 in. x 3/4-in. diameter
nipple and a 2-in. x

3

/4-in. diameter pipe nipple are coupled
to standard 3/4-in. diameter elbows to provide a straight path
down through holes in unit base rails (see Fig. 10). A trap at
least 4-in. deep must be used.

—3—

Table 1 — Physical Data

UNIT SIZE 542J 150 180
NOMINAL CAPACITY (tons) 12

1

/

2

15

OPERATING WT (lb)

Al/Al* 1615 1925
Al/Al Coated* 1615 1925
Unit Al/Cu* 1745 2075

Cu/Cu* 1815 2165
Electric Heat 65 65
EconoMi$erIV 90 90
Roof Curb† 200 200

COMPRESSOR Semi-Hermetic

Type (Number) 06D-328 (1) 06D-818 (2)
Cylinders 64
Oil Change (oz.) (each circuit) 115 88

REFRIGERANT TYPE R-22

Charge (lb)

System 1 26.0 16.5
System 2 — 16.5

3

OUTDOOR COIL

Rows 33

/8 in., Internally Grooved Copper T ubes, Aluminum or Copper Lanced Fins

Fins/in. 15 15
Total Face Area (sq ft) 21.7 21.7

OUTDOOR FAN Propeller Type, Direct Drive

Nominal Cfm 9,000 9,000
Number...Diameter (in.) 3...22 3...22
Motor Hp (1075 rpm)
Watts Input (Total) 1090 1090

INDOOR CO IL

Expansio n D ev i c e Fixed Orifice

3

/8 in., Internally Grooved Copper Tubes, Aluminum or Copper Lanced Fins, Face Split

1

/

2

1

/

2

Rows 33
Fins/in. 15 15
Total Face Area (sq ft) 17.5 17.5

INDOOR FAN Centrifugal, Adjustable Pitch Belt Drive

Quantity...Size (in.)
Nominal Cfm 5000 6000

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

Maximum Continuous Bhp 4.25 5.90
Fan Rpm Range 862-1132 799-1010
Maximum Allowable Rpm 1550 1550
Motor Pulley Pitch Diameter (in.) 3.1/4.1 3.7/4.7
Fan Pulley Pitch Diameter (in.)
Belt, Quantity...Type...Length (in.) 1...BX...42 1...BX...46
Pulley Center Line Distance (in.) 13.5-15.5 13.3-14.8
Speed Change Per Turn (rpm)

6.0 11.4

54 42

Pulley Maximum Full Turns 6** 6**
Factory Pulley Turns Setting 33
Factory Speed Setting (rpm) 1024 926
Fan Shaft Diameter (in.)
Motor Hp (Service Factor) 3.7 (1.15) 5.0 (1.15)
Motor Frame Size 56H 184T
Motor Efficiency 0.84 0.84

3

/

1

16

17/

16

HIGH-PRESSURE SWITCH

Cutout (psig) 426
Reset (psig) 320

LOW-PRESSURE/LOSS-OF-CHARGE
SWITCH

Cutout (psig) 7
Reset (psig) 22

AIR INLET SCREENS Cleanable

Economi zer, Quantity...Size (in.)

RETURN-AIR FILTERS (TYPE) 10% Efficient — 2-in. Throwaway Fiberglass

Quantity...Size (in.)

DEFROST THERMOSTAT

Defrost Time 30 min (Adjustable to 50 or 90 min)

2...20 x 25 x 1

1...20 x 20 x 1

4...20 x 20 x 2

4...16 x 20 x 2

Closes (F) 28
Opens (F) 65

LEGEND

Al — Aluminum
Cu — Copper

*Indoor coil fin material/outdoor coil fin material.

†Weight of 14 in. roof curb.

**Pulley cannot be run at 0 or

1

/2 turns open.

—4—

NOTES:

1. Refer to print for roof curb accessory dimensions.

2. Dimensions in ( ) are in millimeters.

3. Center of Gravity.

4. Direction of airflow.

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

6. Minimum clearance:

•Rear: 7′-0″ (2 134) for coil removal. This dimension
can be reduced to 4′-0″ (1219) if conditions per mit
coil removal from the top.

• Left side: 4′-0″ (1219) for proper outdoor coil airflow.

• Front: 4′-0″ (1219) for control box access.

• Right side: 4′-0″ (1219) for proper operation of
damper and power exhaust (if so equipped).

• Top: 6′-0″ (1829) to assure proper outdoor fan
operation.

• Local codes or jurisdiction may prevail.

7. With the exception of clearance for the outdoor coil
and the damper/power exhaust as stated in note
no. 6, a removable fence or barricade requires no
clearance.

8. Dimensions are from outside of cor ner post. Allow

5

/

″ (8) on each side for top cover drip edge.

0′-

16

9. A 90 degree elbow must be installed on the supply
ductwork below the unit discharge for units
equipped with electric heat.

STANDARD UNIT

WEIGHT

ECONOMI$ERIV

WEIGHT

1615 lb (733 kg) 90 lb (41 kg)

Fig. 4 — Base Unit Dimensions — 542J150

—5—

NOTES:

1. Refer to print for roof curb accessory dimensions.

2. Dimensions in ( ) are in millimeters.

3. Center of Gravity.

4. Direc tion of airflow.

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

6. Minimum clearance:

• Rear: 7′-0″ (2134) for coil removal. This dimension
can be reduced to 4′-0″ (1219) if conditions per mit
coil removal from the top.

• Left side: 4′-0″ (1219) for proper outdoor coil airflow.

•Front: 4′-0″ (1219) for control box access.

• Right side: 4′-0″ (1219) for proper operation of
damper and power exhaust (if so equipped).

• Top: 6′-0″ (1829) to assure proper outdoor fan
operation.

• Local codes or jurisdiction may prevail.

7. With the exception of clearance for the outdoor coil
and the damper/power exhaust as stated in note
no. 6, a removable fence or barricade requires no
clearance.

8. Dimensions are from outside of corner post. Allow

5

/

″ (8) on each side for top cover drip edge.

0′-

16

9. A 90 degree elbow must be installed on the supply
ductwork below the unit discharge for units
equipped with electric heat.

STANDARD UNIT

WEIGHT

ECONOMI$ERIV

WEIGHT

1925 lb (874 kg) 90 lb (41 kg)

Fig. 5 — Base Unit Dimensions — 542J180

—6—

NOTE: Do not drill in this area, as damage to basepan may result in
water leak.

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

(542J180 Shown)

VI. STEP 6 — MAKE ELECTRIC CONNECTIONS
A. Field Power S upply

Unit is factory wired for voltage shown on nameplate.
When installing units, provide a disconnect of adequate size

per NEC (National Electrical Code) requirements (Table 2).
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.

Transformers no. 1 and 2 are wired for 230-v unit. If 208/
203-v unit is to be run with 208-v power supply, the trans­formers must be rewired as follows:

1. Remove cap from red (208 v) wire.

2. Remove cap from orange (230 v) spliced wire.

3. Replace orange wire with red wire.

4. Recap both wires.

IMPORTANT: BE CERTAIN UNUSED WIRES ARE
CAPPED. Failure to do so may damage the transformers.

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 w ith in 10%.

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

Perce nt ag e of Voltage Imbalance

NOTE: Do not drill in this area, as damage to basepan may result in
water leak.

Fig. 7 — Concentric Duct Air Distribution

(542J180 Shown)

Shaded area indicates block-off panels.

NOTE: Dimensions A, A′ and B, B′ are obtained from field-supplied
ceiling diffuser.

Fig. 8 — Concentric Duct Details

= 100 x

max voltage deviation from average voltage

average voltage

EXAMPLE: Supply voltage is 460-3-60.

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

Average Voltage =

455 + 464 + 455

1371

=

3

3

= 457

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 the percent voltage imbal ance:

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%.

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.

—7—

INDOOR FAN MOTOR ACCESS

FILTER
ACCESS

3/4" FPT DRAIN
CONNECTION

1-3/8"
DRAIN HOLE

Fig. 9 — Condensate Drain Details

Fig. 10 — Condensate Drain Piping Details

LEGEND

EQUIP GND — Equipment Ground
kcmil — Thousand Circular Mils
NEC — National Electrical
TB — Terminal Block

NOTE: The maximum wire size for TB1 is 350 kcmil f or all unit v olt ages.

Fig. 11 — Field Power Wiring Connections

B. Field Control Wiring

Install a Bryant-approved accessory thermostat assembly
according to th e installation instru ctions included with the
accessory. Refer to unit Price Pages or contact your
local Bryant representative for more information. Locate

thermostat assembly on a solid wall in the conditioned space
to sense average temperature.

Route thermostat cable or equivalent single leads of no. 18
AWG (American Wire Gage) colored wire from subbase te r­minals through conduit in unit to low-voltage connections as
shown on unit label wiring diagram and in Fig. 12.

NOTE: For wire runs up to 50 ft, use no. 18 AWG 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 wi re larger than no. 18
AWG cannot be directly connected to the thermostat and will
require a junction box and splice at the thermostat.

Set heat anticipator settings as indicated in T able 3. Settings
may be changed sligh tly to pr ovide a great er degree of com­fort for a particular installation.

C. Optional Non-Fused Disconnect

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 shipping, the disconnect handle
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 control box door and r e mo ve t he handle and
shaft from shipping location.

2. Loosen the Allen bolt located on the disconnect
switch. The bolt is locat ed on the sq uare hole a nd 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 bo x door.

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 th e end of the shaf t
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 outl et rece ptacle is pr o­vided for field wiring. Field wiring should be run thro ugh th e

7

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

opening.

—8—

Table 2 — Electrical Data

UNIT

542J

150

180

VOLTAGE

(3 Ph,

60 Hz)

208/230 187 253 39.7 228 — — 3 1.7 3.7 10.5/10.5

208/230 187 253 28.2 160 28.2 160 3 1.7 5 15.8/15.8

VOLTAGE

RANGE

Min Max RLA LRA RLA LRA Qty

460 414 508 19.9 114 — — 3 0.8 3.7 4.8

460 414 508 14.1 80 14.1 80 3 0.8 5 7.9

LEGEND

FLA — Full Load Amps
HACR — Heating, Air Conditioning and Refrigeration
LRA — Locked Rotor Amps
MCA — Minimum Circuit Amps
MOCP — M aximum Overcurrent Protection
NEC — National Electrical Code
RLA — Rated Load Amps

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

480 v. If po wer distribution voltage to unit varies from rated heater volt­age, heater kW will vary accordingly.

†Fuse or HACR circuit breaker. This is the maximum size permissible;

smaller fuse size may be used where conditions permit.

COMPRESSOR OUTDOOR

No. 1 No. 2

FAN

MOTOR

FLA

(ea)

INDOOR FAN

MOTOR

Hp FLA FLA LRA FLA kW MCA MOCP† RLA LRA

POWER

EXHAUST

——

4.6 18.8

——

2.3 6.0

——

4.6 18.8

——

2.3 6.0

ELECTRIC HEAT* POWER SUPPLY

—/— —/— 65/ 65 100/100 64/ 64
39/ 45 14/19 114/122 125/150 64/ 64
72/ 82 26/34 155/168 175/175 94/107

117/135 42/56 211/200 225/225 147/167

—/— —/— 70/ 70 100/100 69/ 69
39/ 45 14/19 119/126 125/150 69/ 69
72/ 82 26/34 159/173 175/175 100/112

117/135 42/56 216/205 225/225 152/173

— — 32 50 31
18 15 54 60 31
39 32 81 90 50
66 55 98 110 82

— — 34 50 34
18 15 57 70 34
39 32 83 90 53
66 55 100 110 84

—/— —/— 84/ 84 110/110 89/ 89

117/135 42/56 231/219 250/225 153/173

—/— —/— 89/ 89 110/110 94/ 94

117/135 42/56 235/224 250/225 158/179

— — 42 50 44
66 55 108 110 85

— — 44 50 47
66 55 110 125 88

DISCONNECT

SIZING

387/387

406/406

189

195

499/48572/ 82 26/34 174/187 175/200 101/112

518/50472/ 82 26/34 179/191 200/200 106/118

23839 32 91 100 54

24439 32 93 100 57

NOTES:

1. In compliance with NEC requirements for multimotor and combina­tion load equipment (refer to NEC Articles 430 and 440), the over­current protective device for the unit shall be fuse or HACR
breaker. The Canadian units may be fuse or circuit breaker.

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

Fig. 12 — Field Control Thermostat Wiring

Table 3 — Heat Anticipator Settings

UNIT 542J

150

180

UNIT

VOLTAGE

208/230-3-60

460

208/230

460

HEATER

kW

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

15 .40 —
32 .40 .40
55 .40 .66

26/34 .40 .66
42/56 .66 .40

32 .40 .40
55 .40 .66

6T3 4T2 2T1 LOAD

5L3 3L2 1L1 LINE

STAGE 1 STAGE 2

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

—9—

VII. STEP 7 — MAKE OUTDOOR-AIR INLET ADJUSTMENTS
A. Manual Outdoor-Air Damper

All units (except those equipped with a factory-installed
EconoMi$erIV ) h ave a ma nual out door-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 damper to desired setting. Then
retighten screws to secure damper (Fig. 14).

VIII. STEP 8 — INSTALL OUTDOOR-AIR HOOD
IMPORTANT: If the unit is equipped with the optional

EconoMi$erIV component, move the outdoor-air tempera­ture sensor prior to installing the outdoor-air hood. See the
Optional EconoMi$erIV section for more information.

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

NOTE: The hood top panel, upper and lower filter retainers,
hood drain pan, and filter support bracket are secured oppo­site the outdoor coil end of the unit. The screens, hood side
panels, remaining section of filter support bracket, seal strip,
and all other hardware ar e in a package located inside t he
return-air filter access panel (Fig. 15).

1. Attach seal strip to upper filter retainer. See Fig. 16.

2. Assemble hood top panel and side panels, upper filter
retainer, and hood drain pan (Fig. 17).

3. Secure lower filter retainer and long section of filter
support bracket to unit. See Fig. 17.

4. Loosen sheet metal screws for base unit top panel
located above o utdoor-air inlet opening, and remove

screws for hood side panels located on the sides of the
outdoor-air inlet opening.

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

6. Hold hood side panel flanges flat against unit, and
install screws removed in Step 4.

7. Insert outdoor-air inlet screens and spacer in channel
created by lower filter retainer and filter support
bracket.

8. Attach remaining short section of filter support
bracket.

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.

Fig. 14 — 25% Outdoor-Air Section Details

HOOD TOP
PANEL

Fig. 16 — Seal Strip Location

(Air Hood Cross-Sectional View)

LOWER FILTER
RETAINER

FILTER SUPPORT
BRACKET

FILTER SUPPORT
BRACKET

HOOD SIDE
PANELS (2)

LOWER
FILTER
RETAINER

Fig. 15 — Outdoor-Air Hood Component Location

HOOD DRAIN PAN

UPPER FILTER RETAINER

NOTE: The outdoor-air hood comes with a baffle which is not used on
these units. Discard the baffle.

Fig. 17 — Outdoor-Air Hood Details

—10—

A. Motormaster® I Control Installation

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. 18 for baffle details. Use 20-gage, galvanized sheet
metal, or similar corrosion-resistant metal for baffles. Use
field-supplied screws to at tach baffles t o unit. Screws shou ld

1

be

/4-in. diameter and 5/8-in. long. Drill required screw holes

for mounting baffles.

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

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 ambien t kit (purchased separately). The
Motormaster I device controls outdoor fan no. 1 while ou t­door fans no. 2 and 3 are sequenced off by the accessory 0° F
low ambient kit.

Accessory 0° F Low Ambient K it — Install the accessory 0° F
low ambient kit per instruction supplied with accessory.

Sensor Assembl y — Install the sensor assembly in the loca­tion shown in Fig. 19.

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

Transfor mer (460-V Units On ly) — 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 protruding from bottom of extrusion.

MOTORMASTER
SENSOR
LOCATION

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.

HAIRPIN END

Fig. 19 — Motormaster I Sensor Locations

X. STEP 10 — ADJUST FACTORY-INSTALLED OPTIONS
A. Optional EconoMi$erIV

See Fig. 20 and 21 for EconoMi$erIV component locati ons.
NOTE: These instructions are for installing the optional

EconoMi$erIV only. Refer to the accessory EconoMi$erIV or
EconoMi$er2 installation instructions when field in stalling an
EconoMi$erIV or EconoMi$er2 accessory.

To complete installation of t he optional EconoMi$erIV, per­form the following procedure.

1. Remove the EconoMi$er IV hood. Refer to Step 8 —
Install Outdoor-Air Hood on page 10 for info rmation
on removing and in stalling the outdoor-air hood.

2. Relocate outdoor air temperature sensor from ship­ping position to operation pos ition on EconoMi $erIV.
See Fig. 20.

IMPORTANT: Failure to relocate the sensor w ill res ult in the
EconoMi$erIV not operating properly.

3. Re-install economizer hood.

4. Install all EconoMi$erIV accessories. EconoMi$erIV
wiring is shown in Fig. 22.

Outdoor air leakage is shown in Table 4. Return air pressure
drop is shown in Tabl e 5.

Table 4 — Out door Air Damper Leakage

NOTE: Dimensions in ( ) are in mm.

Fig. 18 — Wind Baffle Details

DAMPER STATIC PRESSURE (in. wg)

0.2 0.4 0.6 0.8 1.0 1.2

LEAKAGE (cfm) 35 53 65 75 90 102

Table 5 — Return Air Pressure Drop (in. wg)

CFM

4500 5000 5400 6000 7200 7500

0.040 0.050 0.060 0.070 0.090 0.100

—11—

SCREWS

ECONOMI$ERIV

FRAME

TOP

SCREWS

OUTDOOR AIR
TEMPERATURE SENSOR
(INSTALLED OPERATION
POSITION)

LOW TEMPERATURE
COMPRESSOR
LOCKOUT SWITCH

ECONOMI$ERIV

SUPPLY AIR
TEMPERATURE SENSOR
LOCATION

Fig. 20 — EconoMi$erIV Component Locations —

End View

ACTUATOR

CONTROLLER
FLANGE

AND SCREWS
(HIDDEN)

1
R
T

R
T

c
a
V
4

2

M
O
C

4
2

_

c
a
V

T

O

H

H
X
E

+

t
e

S

V
0

2

1

V
2

1

1

N

5

N

n

H

i

X

M

E

s
o

P

4

n

P1

e
p

P

O

3

V
C

1

D

x
a

EF

T1

M

T

V
0

1

EF

V
2

V
C

D

V

t

C

e

D

S

V

1

0

Q

1

A

Q
A

V
2

+

e

O

e
r

S

C

F

l
o

O

o

S

C

B

D

+
R
S

A

R

S

Fig. 21 — EconoMi$erIV Component Locations —

Side View

DCV — Demand Controlled Ventilation

LEGEND

IAQ — Indoor Air Quality
LALS— Low Temperature Compressor

Lockout Switch

OAT — Outdoor-Air Temperature
POT — Potentiometer

Potentiometer Default Settings:
Power Exhaust Middle
Minimum Pos. Fully Closed
DCV Max. Middle
DCV Set Middle
Enthalpy C Setting

Fig. 22 — EconoMi$erIV Wiring

NOTES:

1. 620 ohm, 1 watt 5% resistor should be rem oved only when using differential
enthalpy or dry bulb.

2. If a separate field -supplied 24 v transform er is used for the IAQ sensor power
supply, it cannot have the secondary of the transformer grounded.

3. For field-installed remote minimum position POT, remove black wire jumper
between P and P1 and set control minimum position POT to the minimum
position.

—12—