Test User Interface And Electronic Control Board; Electronic Control Board Identification - Friedrich Kuhl KCS12B10A Service Manual

Test User Interface and Electronic Control Board

If the User Interface does not turn on:
1. Make sure the unit has the proper voltage and that it is turned on.
Check power at Terminals L1 and L2. (Refer to Electronic Control
Board Identification, Figure 711)
2. Disconnect the User Interface's wire harness on the control board.
3. Using a voltmeter, check the outer pins on the user interface port
of the electronic control board . There should be 24VDC. (Refer to
Electronic Control Board Identification, Fig 711
4. If there is no voltage, replace the electronic control board.
For Kuhl
For Kuhl Q
For Wallmaster

Electronic Control Board Identification

AMB TEMP SENSOR
ID COIL TEMP SENSOR
OD COIL TEMP SENSOR
DISCH AIR TEMP SENSOR
HIGH PRESSURE
SWITCH/JUMPER
LOW SPEED
FAN
MED SPEED
FAN
HIGH SPEED
FAN
MAX SPEED FAN
COOLING ONLY MODELS
IF INSTALLED ON
MODELS WITH HEAT THIS
IS A POWER RELAY
COMPRESSOR
POWER
73
COMPONENTS TESTING
USER INTERFACE
HPS
FAN 1
RELAY
FAN 2
RELAY
FAN 3
RELAY
FAN 4
RELAY
COMP
RELAY
GROUND
Figure 711 (Electronic Control Board Identification)
5. If 24 VDC is present replace the User Interface and/ or the ribbon
cable.
Reversing
Valve Relay
HEATER
RELAY
N/L2
HEATER
RELAY
L1
(
L1 POWER
115 OR 230
L2 / N
L2 / RV2
RV1
L2 HEATER POWER
L1 HEATER POWER
N / L2