Electrical Troubleshooting Chart - Cooling - Friedrich H)A09K25L Service Manual

eLeCTRICAL TROUBLeshOOTINg ChART - COOLINg

Compressor runs but
Blower/Fan doesn't
Yes
24V at t-stat and
control wiring?
No
Yes
Is Line Voltage present
at Motor Leads?
No
Yes
Check Capacitor, is
Capacitor Good?
No
Yes
Motor should run
No
9k BTU, 12k BTU, & 18k BTU
NO COOLING OPERATION
Insure that Fuses
are good and/or that
Circuit Breakers are
on and voltage is 208/230
O.K.
Set thermostat to
"Cool," and the Temp.
below the present
Compressor and Fan
Fan runs but
Motor should now
Compressor doesn't
No
Yes
See Refrigerant Circuit
diagnosis if unit still is
not cooling properly
Defective t-stat
defective control wiring
or transformer
Problems indicated
in Blower Relay
of board
Replace Capacitor
Possible motor
problem indicated.
Check motor
thoroughly
Possible Compressor
Before continuing
check for Error
Codes, see
electronics control
diagnostics and
test mode, page 15
Nothing operates,
entire system
appears dead
Room Temp.
No
O.K.
Line voltage present
at the Transformer
operate
Yes
24 Volts at
"R" Terminal on board
24 Volts present at
Y terminals on
t-stat and board?
208/230 Volts present
at #1 relay on board?
Supply Circuit
problems, loose
Voltage a minimum of
Connections, or bad
No
Relays/Board
Replace Capacitor
Are Capacitor and (if
and/or Start Assist
so equipped) Start
Device
No
Allow ample time
for pressures to
Pressures Equalized?
No
equalize
problem indicated.
Compressor should
See Compressor
No
Checks
Yes
Check Supply Circuit's
jumper at transformer. If
okay, replace board
Primary
No
Yes
Problems indicated with
Control Transformer
replace board
No
Yes
Problems indicated with
Room Thermostat or
No
Control Wiring
Yes
Replace board
No
Yes
Compressor and fan
motor should now
No
Is Locked Rotor
See Refrigerant
Circuit Diagnosis if
197 Volts?
unit still is not cooling
Yes
Assist good?
Yes
Have System
Yes
run
Yes
operate
Yes
properly
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