2
INSTALLATION
!
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could result in personal injury
or equipment damage.
Puron (R--410A) refrigerant systems operate at higher
pressures than standard R--22 systems. Do not use R--22
service equipment or components on Puron refrigerant
equipment.
PERSONAL INJURY AND EQUIPMENT DAMAGE
HAZARD
Failure to follow this caution may result in personal injury
and / or equipment damage.
DO NOT
operate the unit without a filter or with grille
removed.
CAUTION
!
COMPLETE PRE--INSTALLATION CHECKS
Unpack Unit
Move the unit to final location. Remove unit from carton, being
careful not to damage service valves and grilles.
Inspect Shipment
File a claim with the shipping company if shipment is damaged or
incomplete. Check the unit nameplates to ensure units match job
requirements.
Consider System Requirements
Consult local building codes and NEC for special installation
requirements.
Allow sufficient space for airflow clearance, wiring, refrigerant
piping, and servicing unit. Locate unit so that condenser airflow is
unrestricted on both sides.
Unit may be mounted on a level pad directly on base legs or
mounted on raised pads at support points.
Matching the Heat Pump to an Indoor Unit
The 538B heat pump units can be matched to corresponding
indoor units. The 538B unit can be matched with under--ceiling
and residential fan coils and evaporator coils. Refer to separate
indoor unit literature for more information.
Expansion Device -- Ducted System Cooling Mode
A hard shutoff, thermostatic expansion valve (TXV) is required at
the indoor section of the system for proper operation of these
products. If the indoor section of the system is not equipped with a
hard shutoff TXV, refer to Spec Sheet for the correct TXV kit to be
installed. Follow the instructions in the kit for proper installation.
Expansion Device -- Duct Free System Cooling Mode
A piston is used as the metering device when installing a
40QAQ018--048 under--ceiling indoor unit. Refer to the indoor
unit instructions for details.
Check AccuRater Metering Device -- Heating Mode
The correct AccuRater (bypass type) refrigerant control is required
for system capacity optimization. An AccuRater device with
field--replaceable piston is supplied with the outdoor unit (see Fig.
2).
Do not
interchange components between the AccuRater device
types. Matching of outdoor unit with indoor unit may require field
replacement of piston. Replace piston, if required, before
connecting refrigerant lines. See Fig. 2. Piston replacement
instructions are included in the indoor unit installation instructions.
After system installation is complete, see the Refrigerant Charging
section in this document to check and/or adjust refrigerant charge.
*
NOTE:
Piston Orientation - Install tapered end
of piston in the direction of the outdoor equipment
for proper heating operation
*
A07407n
Fig. 2
---
AccuRater (bypass type)
Metering Device Components
RIG AND MOUNT UNIT
Mounting on Ground
Mount unit on a solid, level concrete pad. Position unit so water or
ice from roof does not fall directly onto unit. Use field--provided
snow stand or ice rack where prolonged subfreezing temperatures
or heavy snow occurs.
If conditions or local codes require unit be fastened to a pad, 6
field--supplied tie--down bolts should be used and fastened through
slots provided in unit mounting feet.
Mounting on Roof
Mount unit on a level platform or frame at least 6 in. (152.4 mm)
above roof surface. Isolate unit and tubing from structure.
Clearance Requirements
With coil facing wall: Allow 6” (152.4 mm) minimum clearance
on coil side and coil end and 36” (914.4 mm) minimum clearance
on compressor end and fan side
With fan facing wall: Allow 8” (203.2 mm) minimum clearance on
fan side and coil end and 36” (914.4 mm) minimum clearance on
compressor end and coil side.
With multi--unit application: Arrange units so discharge of one
does not enter inlet of another.
IMPORTANT
: When installing multiple units, ensure the
discharge air from one unit is not drawn into another unit. When
installing single or multiple units in an alcove, roof well or partially
enclosed area, ensure there is adequate ventilation to prevent
recirculation of discharge air.
Operating Ambient
Minimum outdoor operating ambient in cooling mode is 55
_
F
(13
_
C), maximum 125
_
F (52
_
C).
Rigging
PERSONAL
INJURY
AND/OR
EQUIPMENT
DAMAGE HAZARD
Failure to follow this caution may result in personal injury
and/or equipment damage.
Be sure unit panels are securely in place prior to rigging.
CAUTION
!
Keep the unit upright and lift unit using a sling. Use cardboard or
padding under the sling, and spreader bars to prevent sling damage
to the unit. See Fig. 3. Install the unit so that the coil does not face
into prevailing winds. If this is not possible and constant winds
above 25 mph are expected, use accessory wind baffle. See
installation instructions provided with the accessory kit.
538B
