Friedrich R410A manual Electrical Troubleshooting Chart Cooling, 9K BTU, 12K BTU, & 18K BTU

ELECTRICAL TROUBLESHOOTING CHART - COOLING

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

NO COOLING OPERATION

SCENARIO 2

Compressor runs but Blower/Fan doesn't

Yes

24V at t-stat and

control wiring?

Yes

									Before continuing
									check for Error
					Insure that Fuses
									Codes, see
					are good and/or that				electronics control
					Circuit Breakers are				diagnostics on
				on and voltage is 208/230
									page 16
					O.K.
					Set thermostat to				Nothing operates,
					"Cool," and the Temp.
					below the present				entire system
									appears dead
					Room Temp.
	SCENARIO 1					O.K.	No			Yes
									Line voltage present
					Compressor and Fan
	Fan runs but								at the Transformer
					Motor should now
									Primary		No
	Compressor doesn't		No		operate
		Yes				Yes				Yes
					See Refrigerant Circuit				24 Volts at
								“R” Terminal on board
					diagnosis if unit still is						No
					not cooling properly					Yes
									24 Volts present at
									Y terminals on
											No
									t-stat and board?
										Yes
									3 minute delay done
	Defective t-stat								at control board?		No
No	defective control wiring
	or transformer									Yes
									208/230 volts present
									at compressor’s
											No
									relay on board?
										Yes
								Are wiring connections
									and capacitor good?		No

Yes

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

Problems indicated with

Control Transformer replace board

Problems indicated

with t-stat or

control wiring. Fix.

Wait until done

Replace board

Yes

Repair or replace what is needed

Is Line Voltage present

at Motor Leads?

Yes

Check Capacitor, is

Capacitor Good?

Yes

Motor should run

No

No

No

Problems indicated

in Blower Relay of board

Replace Capacitor

Possible motor

problem indicated.

Check motor

thoroughly

				No
Supply Circuit
		Is Locked Rotor
problems, loose
Connections, or bad		Voltage a minimum of
Relays/Board	No	197 Volts?
				Yes
Replace Capacitor		Are Capacitor and (if
and/or Start Assist
		so equipped) Start
Device
	No	Assist good?
				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

Compressor and fan

motor should now

operate

Yes

See Refrigerant

Circuit Diagnosis if

unit still is not cooling

properly

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