Friedrich air conditioner troubleshooting

Need professional advice on troubleshooting your Friedrich air conditioner? This is exactly what you’ll find in the tables below. Provided you have identified the symptom correctly, you’ll be able to get an insight on the possible cause of malfunction, an also find out how to fix the appliance. Minor issues are often resolved by users without relevant experience, while more serious problems require professional help.

Friedrich KQ08J50A-B air troubleshooting

PROBLEM	POSSIBLE CAUSE	TO CORRECT
	Low voltage.	Check for voltage at compressor. 115 volt and 230 volt units will operate at 10% voltaqe variance
Compressor does not run	Thermostat not set cold enough or inoperative.	Set thermostat to coldest position. Test thermostat and replace if inoperative.
	Compressor hums but cuts off on overload.	Hard start compressor. Direct test compressor. If compressor starts, add starting components.
	Open or shorted compressor windings.	Check for continuity and resistance.
	Open overload.	Test overload protector and replace if inoperative.
	Open capacitor.	Test capacitor and replace if inoperative.
	Inoperative system switch.	Test for continuity in all positions. Replace if inoperative.
	Broken, loose or incorrect wiring.
	Inoperative system switch.	Test switch and replace in inoperative.
	Broken, loose or incorrect wiring.
Does not run.	Open Capacitor.	Test capacitor and replace if inoperative.
	Fan speed switch open.	Test switch and replace if inoperative.
	Inoperative fan motor.	Test fan motor and replace if inoperative. (Be sure internal overload has had time to reset.)
	Undersized unit.
Does not cool, or cools only slightly.	Thermostat open or inoperative.	Set to coldest position. Test thermostat and replace if necessary.
	Dirty filter.	Clean as recommended in Owner’s Manual.
	Dirty or plugged condenser or evaporator coil.	Use steam or detergents to clean.
	Poor air circulation in area being cooled.	Adjust discharge air louvers. Use high fan speed.
	Fresh air or exhaust air door open on applicable models.	Close doors. Instruct customer on use of this feature.
	Low capacity undercharqe.	Check for leak and make repair.
	Compressor not pumping properly.	Check amperage draw against nameplate. If not conclusive, make pressure test.
Unit does not run.	Fuse blown or circuit tripped.	Replace fuse, reset breaker. If repeats, check fuse or breaker size. Check for shorts in unit wiring and components.
	Power cord not plugged in.
	System switch in “Off’ position.	Set switch correctly.
	Inoperative system switch.	Test for continuity in each switch position.
	Loose or disconnected wiring at switch or other components.	Check wiring and connections. Reconnect per wiring diagram.
Evaporator coil freezes up.	Dirty filter.	Clean as recommended in Owner’s Manual.
	Restricted air flow.	Check for dirty or obstructed coil clean as required.
	Inoperative thermostat.	Test for shorted thermostat or stuck contacts.
	Short of refrigerant.	De-ice coil and check for leak.
	Inoperative fan motor.	Test fan motor and replace if inoperative.
	Partially restricted capillary.	Deice coil. Check temperature differential across coil. Touch test coil return bends for same temperature. Test for low running current.
Compressor runs continually.	Excessive heat load.	Unit undersized. Test cooling performance of unit. Replace with larger unit.
Does not cycle off.	Restriction in line.	Check for partially iced coil. Check temperature split across coil.
	Refrigerant leak.	Check for oil at silver soldered connections.
		Check for partially iced coil. Check split across coil. Check for low running amperage.
	Thermostat contacts stuck	Check operation of thermostat. Replace if contacts remain closed.
	Thermostat incorrectly wired.
Thermostat does not turn unit off.	Thermostat contacts stuck.	Replace thermostat.
	Thermostat set at coldest point.	Turn to higher temperature setting to see if the unit cycles off.
	Incorrect wiring.
	Unit undersized for area to be cooled.
Compressor attempts to start, or runs for short periods only. Cycles on overload.	Overload inoperative. Opens too soon.	Check operation of unit. Replace overload if system operation is satisfactory.
	Compressor attempts to start before system pressures are equalized.	Allow a minimum of two (2) minutes for pressures to equalize before attempting to restart. Instruct customer of waiting period.
	Low or fluctuating voltage.	Check voltage with unit operating. Check for other appliances on circuit. Air conditioner should be on separate circuit for proper voltage, and be fused separately.
	Incorrect wiring.
	Shorted or incorrect capacitor.	Check by substituting a known good capacitor of correct rating.
	Restricted or low air flow through condenser coil.	Check for proper fan speed or blocked condenser.
	Compressor running abnormally hot.	Check for kinked discharge line or restricted condenser. Check amperage.
Thermostat does not turn unit on.	Loss of charge in thermostat bulb.	Place jumper across thermostat terminals to check if unit operates. If unit operates, replace thermostat.
	Loose or broken parts in thermostat.	Check as above.
	Incorrect wiring.
Noisy operation.	Poorly installed unit.
	Fan blade striking chassis.	Reposition adjust motor mount.
	Compressor vibrating.	Check that compressor grommets have not deteriorated. Check that compressor mounting parts are not missing.
	Improperly mounted or loose cabinet parts.	uneck assemoiy ana parts tor looseness, ruDDing and rattling.
Water leaks into room.	Evaporator drain pan overflowing.	Clean obstructed drain trough.
	Condensation forming on base pan.	Evaporator drain pan broken or cracked. Reseal or replace.
	Poor installation resulting in rain entering room.	Keseal as required.
	Condensation on discharge grilles.	Dirty evaporator coil clean. Very high humidity level.
Thermostat short cycles.	Thermostat differential too narrow.	Replace thermostat.
	Plenum gasket not sealing, allowing discharge air to short cycle thermostat.	Check gasket. Reposition or replace.
	Restricted coil or dirty filter.	Clean and advise customer of periodic cleaning of filter.
	Tubular insulation missing from top of thermostat bulb.	Replace tubular insulation on bulb. (Applicable models.)
	Thermostat bulb touching thermostat bulb support bracket.	Adjust bulb bracket. (Applicable models.)
Prolonged off-cycles. (automatic operation)	Anticipator (resistor) wire disconnected at thermostat or system switch.
	Anticipator (resister shorted or open). (Applicable models.)	Disconnect plug from outlet. Remove resistor from bracket. Insert plug and depress “Cool” and “Fan Auto (MoneySaver)” buttons. Place thermostat to warmest setting. Feel resistor for temperature. If no heat, replace resistor.
	Partial loss of charge in thermostat bulb causing a wide differential.	Replace thermostat.
Switches from cooling to heating.	Thermostat sticking.	Change room thermostat.
	Incorrect wiring.
Outside water leaks.	Evaporator drain pan cracked or obstructed.	Repair, clean or replace as required.
	Water in compressor area.	Detach shroud from pan and coil. Clean and remove old sealer. Reseal, reinstall and check.
	Obstructed condenser coil.	Steam clean.
	Fan blade and slinger ring improperly positioned.	Adjust fan blade to 1/2″ clearance from condenser coil.
High indoor humidity.	Insufficient air circulation in air conditioned area.	Adjust louvers for best possible air circulation
	Oversized unit.	Operate in “Fan-Auto (MoneySaver)” position.
	Inadequate vapor barrier in building structure, particularly floors.	Advise customer.
No heating; fan operates.	Thermostat setting.	Set thermostat to a warmer position.
	Defective thermostat.	Replace — do not attempt to adjust.
	Compressor not operating.	Check compressor wiring. Check for open internal or external overload. Check wiring.
	Defective system switch.	Test system switch
Insufficient heating.	Restricted filter.	Clean as recommended in Owner’s Manual.
	Outdoor thermostat. (Applicable models.)	Check if outdoor thermostat is energizing the heating element at its predetermined temperature setting
	Fresh air or exhaust door open.	Check control setting.
Fan operates in “constant” position, but not in “automatic” (MoneySaver).	Inoperative system switch.	Check continuity of switch.
	Incorrect wiring.	Check applicable wiring diagram.
Temperature varies from comfortable to overly warm.	Defective thermostat.	Incorrect differential setting. Replace thermostat.
	Heat anticipator (resistor) shorted. (Applicable models)	Check voltage to resistor. If voltage okay, remove resistor from thermostat bulb block. With current on, feel resistor for warmth. If no heat can be felt, replace anticipator.
Room temperature uneven. (Heating cycle)	Heat anticipator (resistor) shorted. (Applicable models.)	Disconnect power to unit. Remove resistor from thermostat bulb block. Plug in unit and allow to operate. Feel resistor for heat. If no heat is felt, replace resistor.
	Wide differential — partial loss of thermostat bulb charqe.	Replace thermostat and check.
	Incorrect wiring.	Resistor is energized during the “on” cycle of compressor or fan.
Unit will not defrost.	Incorrect wiring.
	Defrost control timer motor not advancing.	Check for voltage at “TM” and “TM1” on timer. If voltaqe. replace control.
	Defrost control out of calibration.	If outside coil temperature is 25° F or below, and pre-selected time limit has elapsed, replace the defrost control.
	Defrost control contacts stuck.	If the contacts remain closed between terminals “2” and “3” of the defrost control after pre-selected time interval has passed, replace control.
	Defrost control bulb removed from coil, or not making good coil contact.	Reinstall and assure that good bulb to coil contact is made.
Unit does not heat adequately.	Outdoor thermostat does not cut off compressor at the pre-selected temperature and bring on the heating element.	Defective thermostat — replace.
	Fresh air or exhaust door open.	Check if operating properly. Instruct customer on proper use of control.
	Dirty filter.	Clean as recommended in Owner’s Manual
	Unit undersized.	Check heat rise across coil. If heat rise is satisfactory, check if insulation can be added to attic or walls.
Unit cools when heat is called for.	Incorrect wiring.
	Defective solenoid coil.	Check for continuity of coil.
	Reversing valve fails to shift.	Block condenser coil and switch unit to cooling. Allow pressure to build up in the system, then switch heatinq. If valve fails to shift, replace valve.
	Inoperative system switch.	Check for continuity of system switch.
Cooling adequate —heating insufficient.	Heating capillary tube partially restricted.	Check for partially starved outer coil. Replace heatir c capillary tube.
	Check valve leaking internally.	Switch unit several times from heating to cooling. Check temperature rise across the coil.
	Reversing valve failing to shift completely — bypassing hot gas.	De-energize solenoid coil, raise head pressure, energize solenoid to break loose. If valve fails to make complete shift, replace valve.
Compressor will not turn off and operate on heating element only during low outside ambients.	Outdoor thermostat. (Applicable models.)
Compressor shuts off on outdoor thermostat but element does not heat.	Fuse link.	Check fuse link for continuity. If defective, replace. Check amperage draw of element. If no amperage, replace.
	Heating element shorted.	Check voltaqe to element. If voltaqe is okay, check winng.
	Incorrect wiring.	Defective coil. Test coil for continuity.
	Heat relay or heater contactor coil open.
Fan operates -heating element does not come on.	Heater relay or contactor coil open.	Check continuity of coil.
	Heater relay or contactor stuck open, pitted or burned.	Inspect, test continuity with ohmmeter.
	High limit control open.	Check continuity if open, replace.
	Open Thermal fuse.	Check Continuity. Check reason for failure.
	Open or shorted element.	Check voltage across heater terminals. Check amperage draw of heater.
	Loose connections.	Tighten all terminals.
Heating inadequate.	Restricted filter. Cycling high limit control.	Clean as recommended in Owner’s Manual. Control is set to open at 155°F ± 50°F and close at 130°F ± 8°F. If cycling prematurely, replace control.
	Exhaust or fresh air door open.	Check position of fresh air door control slide. Adjust cable if door does not close properly.
Fan operates in the “Constant” position, but not in “Automatic.” (MoneySaver).	Fan relay contacts open.	Check continuity of fan relay. NOTE: Some models have the fan relay energized during the heating cycle while others do not.
	Inoperative system switch.	Check continuity between terminals “L2” and “3” of the system switch.
	Loose connection.	Check connections on system switch and fan relay.
Long “off’ and “on” cycles.	Heat anticipator (resistor) shorted.	Disconnect power to the unit. Remove the resistor from the thermostat bulb block. Plug in the unit and allow to operate. Feel the resistor for heat. If no heat is felt, replace the resistor.
	Defective thermostat.	Replace thermostat and check operation.
Fan motor does not operate in “Constant” or “MoneySaver” position.	Defective motor	Check and replace.
	Open or shorted capacitor.	Replace capacitor and check.
	Condenser tan frozen to base pan.	Check it drain pan valve is open, it not. replace.
	Loose connections.	Check all connections. Check voltage to fan motor
Element does not heat.	Fuse link.	Check fuse link for continuity. If defective, replace.
	Heating element shorted.	Check amperage draw of element. If no amperaqe. replace.
	Incorrect wiring.	Check voltage to element. If voltage is okay, check wirinq.
	Heat relay or heater contactor coil open.	Defective coil. Test coil for continuity.

Friedrich SS08 air troubleshooting

COMPLAINT	CAUSE	SOLUTION
Unit does not operate.	• The unit is turned to the off position, or the thermostat is satisfied.	• Turn the unit to the on position and raise or lower temperature setting (as appropriate) to call for operation.
	• The LCDI power cord is unplugged.	• Plug into a properly grounded 3 prong receptacle.
	• The LCDI power cord has tripped (Reset button has popped out).	• Press and release RESET (listen for click: Reset button latches and remains in) to resume operation.
	• The circuit breaker has tripped or the supply circuit fuse has blown.	• Reset the circuit breaker, or replace the fuse as applicable. If the problem continues, contact a licensed electrician.
	• There has been a local power failure.	• The unit will resume normal operation once power has been restored.
Unit Trips Circuit Breaker or Blows Fuses.	• Other appliances are being used on the same circuit.	• The unit requires a dedicated outlet circuit, not shared with other appliances.
	• An extension cord is being used.	• Do NOT use an extension cord with this or any other air conditioner.
	• The circuit breaker or time-delay fuse is not of the proper rating.	• Replace with a circuit breaker or time-delay fuse of the proper rating. If the problem continues, contact a licensed electrician.
LCDI Power Cord Trips (Reset Button Pops Out).	• The LCDI power cord can trip (Reset button pops out) due to disturbances on your power supply line.	• Press and release RESET (listen for click: Reset button latches and remains in) to resume normal operation.
	• Electrical overload, overheating, or cord pinching can trip (Reset button pops out) the LCDI power cord.	• Once the problem has been determined and corrected, press and release RESET (listen for click: Reset button latches and remains in) to resume normal operation.
Unit Does Not Cool/Heat Room Sufficiently. Or Cycles On And Off Too Frequently.	• The return/discharge air grille is blocked.	• Ensure that the return and/or discharge air paths are not blocked by curtains, blinds, furniture, etc.
	• Windows or doors to the outside are open.	• Ensure that all windows and doors are closed.
	• The temperature is not set at a cool enough/warm enough setting.	• Adjust the Temperature control to a cooler or warmer setting as necessary.
	• The filter is dirty or obstructed.	• Clean the filter, or remove obstruction.
	• The indoor coil or outdoor coil is dirty or obstructed.	• Clean the coils, or remove obstruction.
	• There is excessive heat or moisture (cooking, showers, etc.) in the room.	• Be sure to use exhaust vent fans while cooking or bathing and. if possible, try not to use heat producing appliances during the hottest part of the day.
	• The temperature of the room you are trying to cool is extremely hot.	• Allow additional time for the air conditioner to cool off a very hot room.
Unit Does Not Cool/Heat Room Sufficiently, Or Cycles On And Off Too Frequently (continued).	• The outside temperature is below 60° F (16® C).	• Do not try to operate your air conditioner in the cooling mode when the outside temperature is below 60® F (16® C). The unit will not cool properly, and the unit may be damaged.
	• The digital control is set to fan cycling mode.	• Since the fan does not circulate the room air continuously at this setting, the room air does not mix as well and hot (or cold) spots may result. Using the continuous fan setting is recommended to obtain optimum comfort levels.
	• The air conditioner has insufficient cooling capacity to match the heat gain of the room.	• Check the cooling capacity of your unit to ensure it is properly sized for the room in which it is installed. Room air conditioners are not designed to cool multiple rooms.
	• The air conditioner has insufficient heating capacity to match the heat loss of the room.	• Check the heating capacity of your unit. Air conditioners are sized to meet the cooling load, and heater size is then selected to meet the heating load. In extreme northern climates, room air conditioners may not be able to be used as a primary source of heat.
Unit Runs Too Much.	• This may be due to an excessive heat load in the room.	• If there are heat producing appliances in use in the room, or if the room is heavily occupied, the unit will need to run longer to remove the additional heat.
	• It may also be due to an improperly sized unit.	• Be sure to use exhaust vent fans while cooking or bathing and, if possible, try not to use heat producing appliances during the hottest part of the day.
	• This may be normal for higher efficiency (EER) air conditioners.	• The use of higher efficiency components in your new air conditioner may result in the unit running longer than you feel it should. This may be more apparent, if it replaced an older, less efficient, model. The actual energy usage, however, will be significantly less when compared to older models.
	• You may notice that the discharge air temperature of your new air conditioner may not seem as cold as you may be accustomed to from older units. This does not, however, indicate a reduction in the cooling capacity of the unit.	• The energy efficiency ratio (EER) and cooling capacity rating (Btu/h) listed on the unit’s rating plate are both agency certified.

Friedrich CP05N10 air troubleshooting

COMPLAINT	CAUSE	REMEDY
Fan motor will not run.	No power	Check voltage at outlet. Correct if none.
	Power supply cord	Check voltage to electronic control board. If none, check power supply cord. Replace cord if circuit is open.
	Wire disconnected or connection loose	Connect wire. Repair or replace loose terminal.
	Capacitor (Discharge capacitor before testing.)	Test capacitor. Replace if not within ±10% of manufacturer’s rating. Replace if shorted, open, or damaged.
	Will not rotate	Fan blade hitting shroud or blower wheel hitting scroll. Re-align assembly. Units using slinger ring condenser fans must have 1/4″ inch clearance to the base. If necessary, shim up the bottom of the fan motor with mounting screw(s). Check fan motor bearings; if motor shaft will not rotate, replace the motor.
Fan motor runs.	Revolves on overload	Check voltage. If not within limits, call an electrician. Test capacitor. Check bearings. Does the fan blade rotate freely? If not. replace fan motor. Pay attention to any change from high speed to low speed. If the speed does not change, replace the motor.
Fan motor noise.	Fan blade	If cracked, out of balance, or partially missing, replace it.
	Blower wheel	If cracked, out of balance, or partially missing, replace it.
	Loose set screw	Tighten it.
	Worn bearings	If knocking sounds continue when running replace the motor. If the motor hums or noise appears to be internal while running, replace motor.
Compressor will not run, fan motor runs.	Voltage	Check voltage. If not within limits, call an electrician.
	Wiring	Check the wire connections; if loose, repair or replace the terminal. If the wires are discon- nected, Check the wire connections; If not according to the wiring diagram, correct the connections.
	Thermistor	Check the TEMP control. If not at the lowest number, set TEMP control to this setting.
		Check the continuity of the thermistor. Replace the control board if the circuit is open.
	Capacitor (discharge capacitor before servicing.)	Check the capacitor. Replace if not within ±10% of manufacturer’s rating, replace if shorted, open, or damaged.
	Compressor	Check the compressor for open circuit or ground. If open or grounded, replace the compressor.
	Overload	Check the compressor overload if externally mounted. Replace if open. (If the compressor temperature is high, remove the overload, cool, and retest.)
Compressor cycles on overload.	Voltage	Check the voltage. If voltage is not within these limits, call an electrician.
	Overload	Check overload, if externally mounted. Replace if open. (If the compressor temperature is high, remove the overload, cool, and retest.)
Compressor cycles on overload.	Fan motor	If not running, determine the cause. Replace if required.
	Condenser air flow restriction	Remove the cabinet, inspect the interior surface of the condenser. If restricted, clean carefully with a vacuum cleaner (do not damage fins) or brush. Clean the interior base before re-assembling.
	Condenser fins (damaged)	If the condenser fins are closed over a large area on the coil surface, head pressures will increase, causing the compressor to cycle. Straighten the fins or replace the coil.
	Capacitor	Test the capacitor.
	Wiring	Check the terminals. If loose, repair or replace.
	Refrigeration system	Check the system for a restriction.
Insufficient cooling	Air filter	If restricted, clean or replace.
	Unit undersized	Determine if the unit is properly sized for the area to be cooled.
Excessive noise	Blower or fan	Check the set screw, or clamp. If loose or miss- ing. correct. If the blower or fan is hitting scroll or barrier, rearrange the air handling parts.
	Copper tubing	Remove the cabinet and carefully rearrange the tubing not to contact the cabinet, compressor, shroud, and barrier.

Friedrich CP08 air troubleshooting

Problem	Possible Causes	What To Do
Air conditioner does not start	■ The air conditioner is unplugged.	• Make sure the air conditioner plug is pushed completely into the outlet.
	■ The fuse is blown/circuit breaker is tripped.	• Check the house fuse/circuit breaker box and replace the fuse or reset the breaker.
	■ Power failure.	• It power failure occurs, turn the Mode Control to Off. When power is restored, wait 3 minutes to restart the air conditioner to prevent tripping of the compressor overload.
	■ The current interrupter device is tripped.	• Press the RESET button located on the power cord plug. If the RESET button will not stay eng aged, discontinue use of the air conditioner and contact a qualified service technician.
Air conditioner does not cool as it should	■ Airflow is restricted.	• Make sure there are no curtains, blinds, or furniture blocking the front of the air conditioner.
	■ The THERMOSTAT may not be set high enough.	•Turn the knob to a higher setting. The highest setting provides maximum cooling.
	■ The air filter is dirty.	• Clean the filter at least every 2 weeks.
	■ The room may have been hot.	• When the air conditioner is first turned on you need to allow time for the room to cool down.
	■ Cold air is escaping.	• Check for open furnace floor registers and cold air returns. • Set the air conditioner’s vent to the closed position.
	■ Cooling coils have iced up.	• See Air Conditioner Freezing Up below.
Air conditioner freezing up	■ Ice blocks the air flow and stops the air conditioner from cooling the room.	• Set the air conditioner’s vent to the closed position.