Fault Code
Defect code Defect explanation
Ed Evaporator de-frosting defect.
AS Indoor ambient temperature sensor failure in heating, cooling, dry and auto
mode.
HS DAHT sensor failure in heating mode.
LO Sensor disconnection malfunction in fan only mode
HI Sensor short circuit malfunction in fan only mode
6. COMPONENT OPERATION & TESTING
WARNING:
DISCONNECT THE POWER CORD FROM THE POWER PLUG BEFORE SERVICING OR
TESTING.
6.1 COMPRESSORS
Compressors are single phase, 115 or 230/208 volt, depending on the model number. All
compressor motors are permanent split capacitor type using only a running capacitor across
the start and run terminal.
All compressors are internally spring mounted and externally mounted on rubber isolators.
COMPRESSOR WINDING TEST (See Figure 1)
Remove compressor terminal box cover and disconnect
wires from terminals. Using an ohmmeter, check
continuity across the following:
1. Terminal "C" and "S" - no continuity
- open winding - replace compressor.
2. Terminal "C" and "R" - no continuity
- open winding - replace compressor.
3. Terminal "R" and "S" - no continuity
- open winding - replace compressor. Figure 1: Compressor winding test
GROUND TEST
Use an ohmmeter set on its highest scale. Touch
one lead to the compressor body (clean point of
contact as a good connection is a must) and the
other probe in turn to each compressor terminal
(see Figure 2.) If a reading is obtained, the
compressor is grounded and must be replaced. Figure 2: Typical ground test
Service Manual
Room Air Conditioner with R-410A
Heat Controller, Inc.
9