Friedrich 000 BTU'S Electrical Troubleshooting Chart Cooling, 9K BTU, 12K BTU, & 18K BTU

ELECTRICAL TROUBLESHOOTING CHART - COOLING

9K BTU, 12K BTU, & 18K BTU

NO COOLING OPERATION

Compressor runs but Blower/Fan doesn't

Yes

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

								Before continuing
								check for Error
				Insure that Fuses
								Codes, see
				are good and/or that				electronics control
				Circuit Breakers are				diagnostics and
			on and voltage is 208/230
								test mode, page 15
				O.K.
				Set thermostat to				Nothing operates,
				"Cool," and the Temp.
								entire system
				below the present
								appears dead
				Room Temp.
					O.K.	No			Yes
								Line voltage present
				Compressor and Fan
Fan runs but				Motor should now				at the Transformer
								Primary		No
Compressor doesn't		No		operate
	Yes				Yes				Yes
								24 Volts at
				See Refrigerant Circuit
							“R” Terminal on board
										No
				diagnosis if unit still is
				not cooling properly					Yes
								24 Volts present at
								Y terminals on		No
								t-stat and board?
									Yes
							208/230 Volts present
Defective t-stat							at #1 relay on board?			No
defective control wiring
or transformer									Yes

					No
Problems indicated
in Blower Relay
of board	Supply Circuit		Is Locked Rotor
	problems, loose
	Connections, or bad		Voltage a minimum of
		No
	Relays/Board		197 Volts?
Replace Capacitor					Yes
	Replace Capacitor		Are Capacitor and (if
	and/or Start Assist		so equipped) Start
	Device	No	Assist good?
Possible motor					Yes
problem indicated.
Check motor
thoroughly
	Allow ample time		Have System
	for pressures to	No	Pressures Equalized?
	equalize
					Yes
	Possible Compressor
	problem indicated.		Compressor should
		No
	See Compressor			run
	Checks

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

Replace board

Yes

Compressor and fan

motor should now

operate

Yes

See Refrigerant

Circuit Diagnosis if

unit still is not cooling

properly

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