Carrier Gemini 38AU07 Series, Installation Instructions Manual

7

Fig. 4 — Service Clearance Dimensional Drawing

Do not install the outdoor unit in an area where fresh air

supply to the outdoor coil may be restricted or when recircu-

lation from the condenser fan discharge is possible. Do not

locate the unit in a well or next to high walls.

Evaluate the path and required line length for intercon-

necting refrigeration piping, including suction riser require-

ments (outdoor unit above indoor unit), liquid line lift (out-

door unit below indoor unit) and hot gas bypass line. Relocate

sections to minimize the length of interconnecting tubing.

Although unit is weatherproof, avoid locations that permit

water from higher level runoff and overhangs to fall onto the

unit.

Step 2 — Complete Pre-Installation Checks

CHECK UNIT ELECTRICAL CHARACTERISTICS

Confirm before installation of unit that voltage, amperage

and circuit protection requirements listed on unit data plate

agree with power supply provided.
UN-CRATE UNIT

Remove unit packaging except for the top skid assembly,

which should be left in place until after the unit is rigged into

its final location.
INSPECT SHIPMENT

File a claim with shipping company if the shipment is

damaged or incomplete.
CONSIDER SYSTEM REQUIREMENTS

Consult local building codes and National Electrical Code

(NEC, U.S.A.) for special installation requirements.

Allow sufficient space for airflow clearance, wiring, re-

frigerant piping, and servicing unit. See Fig. 3 for unit dimen-

sions and weight distribution data.

Locate the unit so that the outdoor coil (condenser) airflow

is unrestricted on all sides and above.

The unit may be mounted on a level pad directly on the base

channels or mounted on raised pads at support points. See Fig. 3

for weight distribution based on recommended support points.
NOTE: If vibration isolators are required for a particular installa-

tion, use the data in Fig. 3 to make the proper selection.

Step 3 — Prepare Unit Mounting Support

SLAB MOUNT

Provide a level concrete slab that extends a minimum of

6 in. (150 mm) beyond unit cabinet. Install a gravel apron in

front of condenser coil air inlet to prevent grass and foliage

from obstructing airflow.

Step 4 — Rig and Mount the Unit

RIGGING

These units are designed for overhead rigging. Refer to the

rigging label for preferred rigging method. Spreader bars are

not required if top crating is left on the unit. All panels must

be in place when rigging. As further protection for coil faces,

plywood sheets may be placed against the sides of the unit,

behind cables. Run cables to a central suspension point so

that the angle from the horizontal is not less than 45 degrees.

Raise and set the unit down carefully.

If it is necessary to roll the unit into position, mount the

unit on longitudinal rails, using a minimum of 3 rollers. Ap-

ply force to the rails, not the unit. If the unit is to be skidded

into position, place it on a large pad and drag it by the pad.

Do not apply any force to the unit.

Raise from above to lift the unit from the rails or pad when

unit is in its final position.

After the unit is in position, remove all shipping materials

and top crating.

Step 5 — Determine Refrigerant Line Sizes

Select the recommended line sizes for 38AUZ and 38AUD

unit from the appropriate tables.

Determine the linear length of interconnecting piping re-

quired between the outdoor unit and indoor unit (evaporator).

Consider and identify also the arrangement of the tubing path

(quantity and type of elbows in both lines), liquid line solenoid

size, filter drier and any other refrigeration specialties located

in the liquid line. Refer to the indoor unit installation instruc-

tions for additional details on refrigeration specialties devices.

Determine equivalent line length adjustments for path and

components and add to linear line lengths. See Table 2,

Equivalent Lengths for Common Fittings, for usual fitting

types. Also identify adjustments for refrigeration specialties.

Refer to Part 3 of the Carrier System Design Manual for addi-

tional data and information on equivalent lengths.

LIQUID LIFT

A liquid lift condition exists when the outdoor unit is lo-

cated below the indoor (evaporator) unit and liquid flows ver-

tically up in a portion of the liquid line. The vertical column

of liquid reduces the available state point sub-cooling at the

evaporator coil’s thermal expansion valve. This effect reduc-

es the length of liquid lift (feet of elevation) that a liquid line

size can accommodate. Longer linear tube lengths will also

reduce the amount of liquid lift possible.

Check Tables 7 (38AUZ), 8 (38AUD), and 9

(38AUDC12) for maximum liquid lift capabilities for line

sizes. Reselect the liquid line tube size if necessary. If maxi-

mum available tube size cannot provide the required lift dis-

tance on this installation, relocate the outdoor unit to reduce

the equivalent line length or the lift requirement.

IMPORTANT: DO NOT BURY REFRIGERANT LINES

REAR:
Min 1

8

" (457 mm)

req

u

ired for 

s

ervice

RIGHT:
Min 1

8

" (457 mm)

req

u

ired for 

s

ervice

LEFT:
Min 1

8

" (457 mm)

req

u

ired for 

s

ervice

FRONT:
42” (1067 mm)
req

u

ired for 

s

ervice

NOTE: O

bs

erve req

u

irement

s

 for 

3

9" (914 mm) oper

a

ting 

cle

a

r

a

nce on either Left or Re

a

r coil opening.

CAUTION

UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment dam-

age or improper operation. Never install suction-line filter

drier in the liquid line of a Puron

®

 system.

MODEL POSITION

TABLE

QUANTITY OF LINE 

SETS

38AUZ/ALL

7

1

38AUD/A,B

8

2

38AUD/C

9

2