Friedrich Kuhl KCS12B10A Service Manual page 57

Tips continued
COMPLAINT
Electronic control
board does not turn unit off
Compressor runs for short
periods only.
Unit does not turn on
Noisy operation
Water Leaks into Room
57
TROUBLESHOOTING
CAUSE
Compressor relay contacts stuck
Incorrect wiring
Unit undersized for area to be cooled
Defective thermistor
Incorrect wiring
Shorted or incorrect capacitor
Restricted or low air flow through
condenser coil or evaporator coil
Compressor running abnormally hot
No power
Incorrect wiring
Defective thermistor
Poorly installed
Fan blade striking chassis
Compressor vibrating
Improperly mounted or loose cabinet
parts refrigerant tubes
Evaporator drain pan overflowing
Condensation forming underneath
base pan
Poor installation resulting in rain
entering the room
Condensation on discharge grille
louvers
Chassis gasket not installed
Downward slope of unit is too steep
inward
SOLUTION
Replace electronic control board
Refer to appropriate wiring diagrams
Refer to industry standard sizing chart
Replace thermistor or electronic control board
Refer to appropriate wiring diagram
Test capacitor and replace if needed.
Check for proper fan speed or blocked coils. Correct as
needed.
Check for kinked discharge line or restricted condenser.
Refrigerant overcharge. Check amperage, connections.
Check power supply. Check LCDI plug. Check wire
connections. Check if panel is locked.
Refer to appropriate wiring diagram
Replace thermistor or electronic control board
Refer to Installation Manual for proper installation
Reposition - adjust motor mount
Check that compressor grommets have not deteriorated.
Check that compressor mounting parts are not missing
Check assembly & parts for looseness, rubbing & rattling
pipes, etc.
Clean obstructed drain trough
Evaporator drain pan broken or cracked. Reseal or replace.
No chassis gasket installed. Install chassis gasket
Check installation instructions. Reseal as required
Dirty evaporator coil. Clean coils (See Routine Maintenance)
Environmental phenomena: point supply louvers upward. Put
on high fan.
Install gasket, per Installation manual
Refer to installation manual for proper installation