Bad thermostat ( short cycling)
Low on refrigerant (cycling on a low pressure switch)
Dirty or bad condenser motor (cycling on a high pressure switch)

All 3 are easy to troubleshoot if you have any knowledge of basic
electricity. Just find the appropriate terminals and wire the control out.

In this heat wave and your 3 to 5 minute cycle I am betting on the
thermostat.


"Stormin Mormon" wrote in message
...
I'd do the fin cleaning routine, again. That's my best
diagnosis, from here.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


"Bob" wrote in message
...
I have a 20-year old Frigidaire through the wall air
conditioner.

When first turned on it does a great cooling job. A digital
thermometer right at the outlet is showing 40°F.

After three to five minutes, the compressor turns off and
the cooling
stops.

After maybe 5 minutes the compressor comes back on and cools
for
another 3 to 5 minutes.

I took the unit outdoors and cleaned the fins with a garden
hose and a
fin-cleaning aerosol spray. It is difficult to view the
fins
visually, but I'm fairly sure they are clean. The cleaning
did not
seem to change the cycling time at all.

I'm in a small town and it is a heat wave. It is difficult
to get a
repair person in the best of times---and I'd rather save the
money and
repair it myself if it is something I can handle.

How do I troubleshoot from this point?