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6.
Turn the blower panel 180 degrees so that the blower support
brackets are now at the bottom of the blower.
7.
Insert the blower panel with the blower and motor into the
desired location. Be careful not to damage the refrigerant
coils or any other internal unit components. Screw the panel
into place.
8.
Replace the wires between the blower motor and electrical
box. Make sure to connect wires to the proper speed taps.
9.
Replace the blower access panel.
10. Reconnect power to the unit.
Step 6 — Install Condensate Drain
All units include a condensate drain pan under the evaporator coil.
Units with waterside economizer have an additional condensate
drain pan under the economizer coil. A drain line must be connect-
ed to each drain pain and pitched away from the unit a minimum
of
1
/
-in. per foot to allow the condensate to flow away from the
8
unit.
This connection must be in conformance with local plumbing
codes. A trap must be installed in the condensate line to ensure
free condensate flow. (Heat pumps are not internally trapped.) A
vertical air vent is sometimes required to avoid air pockets. See
Fig. 8.
Fig. 8 — Condensate Drain
The depth of the trap depends on the amount of positive or nega-
tive pressure on the drain pan. A second trap must not be included.
The horizontal unit should be pitched approximately
wards
the
drain
in
condensate removal. (See Fig. 9.)
Fig. 9 — Pitched Unit
/
1
4
both
directions,
to
facilitate
1
/
"
4
Step 7 — Pipe Connections
Depending on the application, there are 3 types of WSHP piping
systems to choose from: water loop, ground-water and ground
loop. Refer to Piping Section of Carrier System Design Manual
for additional information.
All WSHP units use female pipe thread fittings for water con-
nections. Refer to Tables 1 and 2 for connection sizes. When
making piping connections, consider the following:
•
Use a backup wrench when making screw connections to
unit to prevent internal damage to piping.
•
Insulation may be required on piping to avoid condensa-
tion in the case where fluid in loop piping operates at tem-
peratures below dew point of adjacent air.
•
Piping systems that contain steel pipes or fittings may be
subject to galvanic corrosion. Dielectric fittings may be
used to isolate the steel parts of the system to avoid gal-
vanic corrosion.
WATER LOOP APPLICATIONS
Water loop applications usually include a number of units
plumbed to a common piping system. Maintenance to any of these
units can introduce air into the piping system. Therefore, air elimi-
nation equipment comprises a major portion of the mechanical
room plumbing.
The flow rate is usually set between 2.25 and 3 gpm per ton of
cooling capacity. For proper maintenance and servicing, pressure-
temperature (P/T) ports are necessary for temperature and flow
verification.
In addition to complying with any applicable codes, consider the
following for system piping:
•
Piping systems using water temperatures below 50°F re-
quire
1
/
-in. closed cell insulation on all piping surfaces to
2
eliminate condensation.
•
Avoid all plastic to metal threaded fittings due to the po-
tential to leak. Use a flange fitted substitute.
•
Teflon tape thread sealant is recommended to minimize in-
ternal fouling of the heat exchanger.
•
Use backup wrench. Do not overtighten connections.
•
Route piping to avoid service access areas to unit.
•
Flush the piping system prior to operation to remove dirt
and foreign materials from the system.
GROUND LOOP APPLICATIONS
-in. to-
Temperatures between 25 and 110°F and a cooling capacity of
2.25 to 3 gpm of flow per ton are recommended. In addition to
complying with any applicable codes, consider the following for
system piping:
•
Limit piping materials to only polyethylene fusion in the
buried sections of the loop.
•
Do not use galvanized or steel fittings at any time due to
corrosion.
•
Avoid all plastic to metal threaded fittings due to the po-
tential to leak. Use a flange fitted substitute.
•
Do not overtighten connections.
•
Route piping to avoid service access areas to unit.
•
Use pressure-temperature (P/T) plugs to measure flow of
pressure drop.
INSTALLING SUPPLY AND RETURN HOSE KIT
Follow these piping guidelines:
1.
Install a drain valve at the base of each supply and return riser
to facilitate system flushing.
2.
Install shutoff/balancing valves and unions at each unit to per-
mit unit removal for servicing.
3.
Place strainers at the inlet of each system circulating pump.
10
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