Friedrich KUHL R-410A Service Manual page 62

COOLING ONLY ROOM AIR CONDITIONERS: TROUBLESHOOTING TIPS
P o r b e l m
Overload inoperative. Opens too
soon
Compressor restarted before
system pressures equalized
Compressor runs
Low or fl uctuating voltage
for short periods
only. Cycles on
overload Incorrect wiring
Shorted or incorrect capacitor
Restricted or low air flow through
condenser coil or evaporator coil
Compressor running abnormally
hot
P o r b e l m
No power
Unit does not
Incorrect wiring
turn on
Defective thermistor
P o r b e l m
Poorly installed
Fan blade striking chassis
Noisy operation
Compressor vibrating
Improperly mounted or loose
cabinet parts refrigerant tubes
P o r b e l m
Evaporator drain pan overfl owing
Condensation forming underneath
base pan
Poor installation resulting in rain
entering the room
Water leaks into
the room
Condensation on discharge grille
louvers
Chassis gasket not installed
Downward slope of unit is too
steep inward
P o s s b i e l C a u e s
P o s s b i e l C a u e s
P o s s b i e l C a u e s
P o s s b i e l C a u e s
Possible Solution
Check operation of unit. Replace overload if
system operation is satisfactory
Control's default of 3 minutes wait delay timer
inoperative. Replace board.
Check voltage with unit operating. Check for
other appliances on circuit. Air conditioner
should be in a dedicated circuit for proper
voltage & fused separately
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.
Possible Solution
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
Possible Solution
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.
Possible Solution
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. Use pressure wash
or biodegradable cleaning agent to clean.
Environmental phenomena: point supply
louvers upward. Put on high fan.
Install gasket, per Installation manual
Refer to installation manual for proper
installation
61