Form O-Y P/N 273647R5, Page 21
Modulating Cooling
Circuit A has a modulating capacity compressor. Each modulating compressor has
a digital controller. The digital controller in the electrical compartment (See
FIGURE
1
on page 4, and
FIGURE 15,
page 14) is the electronic interface between the com-
pressor and the system controller. The compressor controller is connected to the unit
controller to provide protection and diagnostics for modulating compressor operation.
After a compressor shutdown, a two-minute anti-short cycle timer in the compressor
controller delays the compressor restart. The unit controller has a five-minute com
-
pressor on/off time. The delay times are concurrent so total delay time is five minutes.
Compressor Handling
Do not lift compressor by copper tubing. To prevent internal damage, compressors
must ALWAYS be held upright.
The following instructions include major points of consideration that will ensure proper
installation and protect you from potential personal injury. Please use the following 13
steps as a checklist, taking each item in order before proceeding to the next. If more
information is required, contact your local distributor.
WARNING
To avoid electrical shock, power to the compressor(s) MUST
REMAIN OFF during performance of Steps 1 through 9 below. LOCK
DISCONNECT SWITCH OFF (open).
•
Step 1. Verify Proper Application
Verify that the replacement compressor is identical to the model being replaced.
All system components are matched to the compressor. Replacing a compres-
sor with a model other than the manufacturer specified replacement will void the
product warranty. See part numbers for R-410A compressors in the tables on
page 20.
•
Step 2. Determine Cause of Initial Failure and Remove the
Compressor
In order to prevent a second failure, the cause of the original failure must be
determined. Identify the cause and make the necessary repairs.
CAUTION: DO NOT LIFT compressor by copper tubing; damage will
occur. Compressor must remain upright.
WARNING
Wear eye protection and gloves when handling refrigerant or oil and
when brazing.
a)
BEFORE REMOVING THE FAULTY COMPRESSOR, remove refrigerant
charge using proper recovery procedures. Call 1-800-441-9450 for the name
of the nearest Dupont authorized distributor or 1-800-ASK-KLEA (IGI) for
information on their refrigerant reclaim programs.
b) Disconnect wires. All compressor wiring is connected using a black molded
plastic plug. Remove the plug from the compressor.
c) Open access ports so that pressure does not build up in the system. Before
unbrazing stubs from the compressor, cut suction and discharge tubing with a
tubing cutter.
WARNING
Have a fire extinguisher near. The compressor contains oil. There is a
risk of fire when unbrazing stubs.
Compressor
Replacement
WARNINGS
For your safety, wear eye protection, gloves, and protective clothing
when handling refrigerant and oil and when brazing. Have a fire
extinguisher nearby. See Hazard Levels, page 2.
