Friedrich R410A manual 24K BTU, Electrical Troubleshooting Chart - Cooling, No Cooling Operation

ELECTRICAL TROUBLESHOOTING CHART - COOLING

24K BTU

NO COOLING OPERATION

Compressor and outdoor fan motor run but indoor blower does not run

Yes

Indoor blower runs but outdoor fan motor and compressor do not run

Yes

Insure that Fuses

are good and/or that Circuit Breakers are

on and voltage is 208/230

O.K.

	Set thermostat to
	"Cool," move the Temp.
	lever below the present
	Room Temp.
		O.K.
	Compressor outdoor
	fan motor and indoor
No	blower should now
	operate
		Yes
	See Refrigerant Circuit
	diagnosis if unit still is
	not cooling properly

Before continuing

check for Error

Codes, see

electronics control

diagnostics on

page 16

Nothing operates, entire system appears dead

No Yes

Line voltage present at the Transformer Primary

Yes

24 Volts at

“R” Terminal on board

Yes

24 Volts present at Y terminals on t-stat and board?

Yes

No

No

No

Check Supply Circuit’s jumper at transformer. If okay, replace board

Problems indicated with

Control Transformer replace board

Problems indicated with Room Thermostat or Control Wiring. Fix.

24V at t-stat and

control wiring?

Yes

Is Line Voltage present at Motor Leads?

Yes

Check Capacitor, is Capacitor Good?

Yes

Motor should run

No

No

No

No

Defective t-stat

defective control wiring

or transformer

Problems indicated

in Blower Relay of board

Replace Capacitor

Possible motor problem indicated. Check motor thoroughly

Supply Circuit problems, loose Connections, or bad Relays/Board

Replace Capacitor

and/or Start Assist

Device

3 minute delay done
	on control board?			No
		Yes
208/230 Volts present
at compressor’s relay
				No
on control board?
		Yes
Is compressor/fan
	motor contactor
				No
	closed?
			Yes
	Are wiring,
	connections, and
				No
	capacitor good?
			Yes

	Is Locked Rotor
	Voltage a minimum of
No	197 Volts?
		Yes
	Are Capacitor and (if
	so equipped) Start
No	Assist good?

Wait until done

Replace control board

Replace contactor

Repair or replace

component

Compressor and outdoor fan motor should now operate

Yes

See Refrigerant

Circuit Diagnosis

if unit still is not

cooling properly

			Yes
Allow ample time		Have System
for pressures to	No	Pressures Equalized?
equalize
			Yes
Possible Compressor
problem indicated.		Compressor should
See Compressor	No	run
Checks

37