Component Function and Testing
RS1200001 Rev. 1 22 April 1998
Motor,
condenser psc
Condenser fan moves cooling air across condenser coil
and compressor body.
The condenser motor is in a parallel circuit with the
compressor.
Check resistance across coil.
Motor, ecm
evaporator fan
Motor,
refrigerator fan
Refrigerator fan circulates cold air into refrigerator
compartment.
The refrigerator fan motor is in a series circuit with the
semi conductor switch.
See "Refrigeration and Defrost Component Checks Made at High Voltage
Board" section for D.C. voltage check at high voltage board. Check for
voltage at motor also.
Overload
Relay, PTC With power off check resistance.
Across terminals 2 & 3:
Normal = 3 to 12 ohms
Shorted = 0 ohms
Open = infinite ohms
Switch,
keyboard
Overload is a temperature and current sensing type.
Overload opens when sensing a high current or high
compressor temperature.
After overload opens, overload can require up to 2
hours to reset, depending on ambient temperature and
residual heat load in compressor.
1. Disconnect power to refrigerator.
2. Remove relay cover and pull relay off compressor.
3. Pull overload protector off compressor common terminal.
3. With ohmmeter, check resistance between 1/4 " male terminal and
female pin receptacle terminal which pushes onto compressor common
terminal. At ambient temperature, overload protector should have less
than 1 ohm resistance. An open overload protector will have infinite
resistance.
When voltage is connected and PTC is cooled, current
passes through PTC to the start winding.
After a short time, current will have heated the resistor
in PTC and resistance will rise. This blocks current
flow through PTC.
Start winding remains in the circuit through the run
capacitor.
Solid state relay plugs directly on compressor start and
run terminals. Relay terminals 2 and 3 are connected
within relay. Run capacitor is connected to relay
terminal 3. The L2 side of 120 VAC power is
connected to relay terminal 2.
Evaporator motor moves air across evaporator
coil and throughout refrigerator.
Evaporator fan motor is in a parallel circuit with
compressor, with a delay for warm coil
conditions.
Check resistance from ground connector solder. Trace to motor frame
must not exceed .05 ohms. Check power at connector to evaporator
motor.
Switch
Functions
Continuity
Test
Display On 1 and 3
Freezer Temp 3 and 6
Ref Temp 3 and 7
Warmer 6 and 7
Colder 4 and 6
Vacation 4 and 7
Max Ref 7 and 8
Max Frz 4 and 8
Alarm Off 4 and 5
Display Off 5 and 8