Thermistors Description - Friedrich Kuhl KCS12B10A Service Manual

WARNING
ELECTRIC SHOCK HAZARD
Turn off electric power before service or
installation. Extreme care must be used, if it
becomes necessary to work on equipment with
power applied.
Failure to do so could result in serious injury or
death.

Thermistors Description

The units have 4 sensors (Thermistors). Each thermistor is color
coded and has a different function.
1. Indoor Coil (Yellow) - located on the evaporator coil next to
the power board.
2. Outdoor Coil (Blue) - located on the condenser coil.
3. Discharge Air (Black) - located on the front of the unit in
the discharge air port.
4. Ambient Air (White) - located on the front of the unit in front
of the air intake.
Thermistor Testing
1. Gain access to Electronic Control Board (Refer to Control
Board Replacement.
For Kuhl
For Kuhl Q
For Wallmaster
2. Locate thermistor plug and disconnect from Control Board.
(Refer to Control Board Identification, Fig 711)
3. Check for proper resistance. (
Resistance values).
4. If thermistor is out of tolerance, replace thermistor.
Replace Solid State Relay
Model KCL36B30A are equipped with a solid state relay to handle
the higher current demands of these units. The relay is located on
the inside of the Control Mounting Panel in between the Control
Board and Power Cord.
1) Unplug the unit.
2) Remove wire ties as necessary for slack in electrical wiring.
3) Remove 3 screws from Control Mounting Panel.
4) Carefully pull out panel and you will have access to replace
Capacitor or SSR.
5) Replace Component as necessary.
6) Ensure all electrical connections are correct.
7) Reinstall Control Mounting Panel
8) Secure wiring as necessary.
9) Plug unit back in.
10) Test Unit to ensure problems are corrected.
72
COMPONENTS TESTING
Refer to Thermistor
3 ea Screw
Control
Mounting
Panel
Figure 710 (Access to SSR or Capacitor)