Evaporator motor keeps cutting in and out - Frigidaire FRT21P5A Top Freezer Refrigerator

The obvious thing would be the evaporator fan is bad.

I assume you are talking about the AC compressor. Low gas or low evaporator temperature will cause it to cut out, If it is blowing relative warm air it is low on gas.

If I understand you correctly the compressor is short cycling. The more it does this the worse it gets by causing the compressor to overheat. Sometimes the problem is because the condenser fan or evaporator fan being defective. Pull away from wall and remove cover over compressor unplug and feel top of compressor and if too hot to keep hand there keep unplugged but do examine the evaporator and condenser fan to eliminate them as a reason. The most likely reason is start relay and or start/run capacitor and sometimes a worn out compressor.

Overload relay click here=> 67002527
Run capacitor click here=> 65889-4
Location Click Here=> MBB1952GR Compressor Components
Parts in that photo are marked as 10 overload/relay, 11 is the run capacitor and 3 being condenser fan motor. Condenser and evaporator fan motors do not always stop completely when bad so make sure both run while compressor is running. If this has been helpful please rate if you have more questions please let me know, Thanks Sea Breeze

This is not a fun job, open the hood in the far left hand corner, looking at the engine, is where the blower is. it is behind a plastic cover that has to be cut out. do not cut the cover to the a/c evaporator, rectangular box, once you get it out you can see the blower. it is still difficult to get it out, but you can do it. there are 6 to 8 screws that hold it in. keep taking out the plastic as much as you need to get to the screws. good luck

Which motor are you talking about, as there is a compressor, a condenser fan motor (located with the compressor), and evaporator fan motor?

It cut's back on shortly as the sensed temperature "cut-in" is reached, and the unit tries to cool things down below that set temperature again.

Could be lack of service. The unit depends on a clean evaporator and condenser coil. The "other" motor you hear is the compressor starting or stopping probably due to either a high pressure or low pressure switch, or thermal cut-out.

Yes , motor is bad . May not start , next time cuts off . The fan in the back by the compressor , is called the condensor fan motor . I would suggest cleaning the coils in front at the bottom , of dust , lint , pet hair , etc , before replaceing the fan motor . Also , clean the fan blade before reinstalling the motor .

How to check stuff>
http://www.acmehowto.com/howto/appliance/refrigerator/refrigerator.php

Is the evaporator fan in the freezer running. It blows cold air into the fridge side through a damper in the wall between the freezer and fridge. Make sure the damper is open.

Below the evaporator fan is the evaporator coils. Remove the back cover in the freezer to observe the frost pattern. Light frost everywhere(NORMAL) or a partial pattern of ice(LOW ON FREON) or nothing(LOW FREON OR COMPRESSOR PROBLEM).
. Cut everything off for a few minutes then turn it back on and listen for a click from the compressor relay as the compressor tries to start.
Is the compressor motor running.If no check starter/overload relay.
Check to see if the condenser fan at the back underneath near the compressor is running. If no check fan.

Are the condenser coils near there warm or room temp. should be warm

there is a thermistor switch located in evaporator case(thin black single or 2 wires) that makes the compressor cut in and out (cycle) it monitors evaporator temperature.
check head pressures with air cond charging station or gauge set and monitor pressure on high and low side (150-200kpa on low, 1500-1800kpa on high good average depending on ambient temp) if it is low on gas due to leak this can also keep compressor running longer due to evaporator temp not reaching lowest threshhold to cut compressor out

The following is a general removal procedure of A/C evaporator core. The evaporator is removed differently from different vehicles.
For example, a 1994 Ford Taurus/Mercury Sable instructs you to, "Using a hot knife, cut the top of the air conditioning evaporator housing between the raised outline."

Use a hacksaw or a hot knife to cut the case. Reprinted with the permission of Ford Motor Company.
But a 1993 Ford Probe manual says to simply remove the blower motor and assembly screws before separating the case halves and removing the evaporator.




The following procedure assumes that access to the evaporator has been determined.

• Recover the refrigerant.
• Drain the radiator if the heater hose(s) has to be removed to gain access.
• Remove the heater hose(s), if necessary.
• Remove any wiring harness, heat shields, brackets, covers, and braces that may restrict access to the evaporator core.
• Remove the liquid line at the thermostatic expansion valve (TXV) or fixed orifice tube (FOT).
• Remove the suction line at the evaporator or accumulator outlet.
• Gain access to the evaporator core as outlined in the service manual.
• Lift the evaporator from the vehicle.
• Drain the oil from the evaporator into a calibrated cup.
• For replacement, reverse the preceding procedure. First, replace the oil with the same amount and type you previously drained.