Friedrich CP14N10 用户手册

17

Room temperature 

uneven 

(Heating cycle)

Heat anticipator (resistor) shorted (on applicable 
models)

Disconnect power to unit. Remove resistor from t-
stat bulb block. Plus in unit & allow to operate. Feel 
resistor for heat. If not heat, replace resistor

Wide differential - partial loss of t-stat bulb charge

Replace t-stat & check

Incorrect wiring

Refer to appropriate wiring diagram. Resistor is 
energized during "ON" cycle of compressor or fan.

Unit will not defrost

Incorrect wiring

Refer to appropriate wiring diagram

Defrost control timer motor not advancing 
(applicable models)

Check for voltage at "TM" & "TM1" on timer. If no 
voltage, replace control

Defrost control out of calibration (applicable models)

If outside coil temperature is 25F or below, & 
preselected time limit has elapsed, replace defrost 
control

Defrost control contacts stuck

If contacts remain closed between terminals "2" 
& "3" of the defrost control after preselected time 
interval has passed, replace control

Defrost control bulb removed from or not making 
good coil contact

Reinstall & be assured that good bulb to coil contact 
is made

Does not heat 

adequately

Exhaust or fresh air door open

Check if operating properly. Instruct customer on 
proper use of control

Dirty fi lter

Clean as recommended in Owner's Manual

Unit undersized

Check heat rise across coil. If unit operates 
effi ciently, check if insulation can be added to attic 
or walls. If insulation is adequate, recommend 
additional unit or larger one

Outdoor t-stat open (applicable models)

T-stat should close at 38°F. Check continuity of 
control. If temperature is below 38°F, replace control

Heater hi-limit control cycling on & off

Check for adequate fan air across heater. Check 
control for open at 160°F & close at 150°F

Shorted supplementary heater

Ohmmeter check, approx. 32-35 ohms

Incorrect wiring

Check applicable wiring diagram

Heat / Cool Room Air Conditioners: Troubleshooting Tips