On 9/21/2010 10:36 PM, Lloyd E. Sponenburgh wrote:
fired this volley in
:

Lloyd, I mostly am after trying to understand what is happening, right
now. I have a luxury of having plenty of time, due to having less food
at home that fits onto one fridge.

yep. I have repaired a number of them with the same symptom, but the
symptom can be caused by more than one problem.

As someone else said, a _thoroughly_ frozen-up evaporator can cause the
symptom, because the liquid refrigerant won't boil out of the coil fast
enough to reduce the head pressure before the next cycle is requested.
That's one.

A lot of compressors now come with PTC thermistors in place of the
potential relays they used to employ to switch the start cap out of
circuit. They tend to fail rather easily in a high-humidity environment.

Although they're not terribly expensive, I replace all of them with
potential relays; sometimes scavanged from other similar-sized
compressors, sometimes new.

Then, of course, it's possible the new start cap is failing.

The compressor could be on the way out. If the bearings are getting
sticky or tight, the compressor will be harder to start than it should
be. This eventually manifests itself as a "locked rotor", and nothing
you can do (effectively) will fix that, except replacing the compressor.

Foreign material in the closed system can cause it, too. You didn't say
anything about ever opening it, but flakes of insulation from the
compressor windings and corrosion flaking off the inside of improperly
cleaned or improperly brazed lines can all do it. These, too, are
generally fatal problems, and cannot be fixed merely by replacing the
compressor and re-charging.

LLoyd

I always add a little Supco88 to a system when replacing a compressor in
addition to a product like Acid Away an acid neutralizer. Of course a
refrigerator for home use doesn't need as much as a commercial unit but
it only needs a little to help it. A small dryer with an access valve is
not a bad idea either when a refrigerator compressor is replaced and the
odd fridge that has a starting problem can benefit from an all in one
hard start relay and capacitor package. I know a lot of guys who do a
great job on HVAC equipment who have trouble working on itty bitty
refrigeration units. I prefer the big stuff myself like 60 to 4k tons,
it's easier to work on. 8-)

TDD