Friedrich SH15L30-B, SH20L30-B manual Problem Possible Cause To Correct, Compressor

TROUBLESHOOTING (Continued)

PROBLEM	POSSIBLE CAUSE	TO CORRECT
	Compressor attempts to start	Allow a minimum of two (2) minutes to allow pressures to
	before system pressures are
		equalize before attempting to start.
	equalized.
		Check voltage with unit operating. Check for other
COMPRESSOR	Low or fluctuating voltage.	appliances on the circuit. Unit should be on separate circuit
		for proper voltage, and be fused separately.
ATTEMPTS TO
	Incorrect wiring.	Connect per wiring diagram.
START, OR RUNS
FOR SHORT	Shorted or incorrect capacitor.	Check by substituting a known good capacitor of correct
PERIODS ONLY.		rating.
CYCLES ON	Restricted or low air flow through	Check for proper fan speed or blocked condenser.
OVERLOAD.	condenser coil.
	Compressor running abnormally	Check for kinked discharge line or restricted condenser.
	hot.	Check amperage.
	Overload opens too soon.	Change compressor if all other corrections above are
		normal.
	Thermostat contacts not closing.	Check continuity of thermostat at coldest setting. Jump
		contacts, if compressor runs, replace thermostat.
	Low voltage supply.	Check for nameplate voltage.
	Switch (On-Off) inoperative.	Test for continuity.
COMPRESSOR DOES	Open capacitor.	Check by substituting a known good capacitor of correct
NOT START - FAN		rating.
MOTOR RUNS.	Internal overload open.	Check voltage at compressor terminals. If voltage is
		satisfactory, replace compressor.
	Relay open	Replace relay
	Open or shorted compressor	Check windings for continuity and resistance. Direct test
	windings	compressor. If direct test fails, replace compressor.
	Thermostat open or inoperative.	Set to coldest position. Test thermostat and replace if
		necessary.
	Dirty air filter.	Clean as recommended in Owner’s Manual.
DOES NOT COOL,	Dirty or plugged condenser or	Use steam or detergents to clean.
	evaporator coil.
OR COOLS ONLY
	Poor air circulation in area being
SLIGHTLY.		Adjust air louvers.
	cooled.
	Low capacity - undercharge.	Clean, check for leak and make repair.
	Compressor not pumping properly.	Check amperage draw against nameplate. If not conclusive,
		make pressure test.

9