A/C goes into "run away mode" instead of cycling .. suggestions...
 

This is a two part Bryant Air Conditioner...24,000 btu. model number 513.. with a
through the wall compressor and coil. The second section is ceiling mounted air floor
distribution. Installed in 1994...R22 system. Has had regular preventative maintenance.

The system turns on (several existing problems have been repaired, I think we're looking
at the original problem) ....compressor
starts normallly and runs for a few minutes. When it's time to cycle, compressor
keeps running, getting louder and louder (at which point I shut it off). After
waiting a period of time, the system can be started again and the
process repeats itself. Starts normal and then runs on.

It does cool properly....and the fans are operable both in auto and cont mode.
This is a cooling only unit.... (not a heat pump)

Coils have been cleaned. A diagnosis was made about the flare connection
to the metering valve leaking like a "sieve", but I think this problem might have
been introduced into the system during diagnosis, as the freon level was measured
to be acceptable.

Any leads as to where the problem might be ???

Thanks in advance !!!

Peter

A/C goes into "run away mode" instead of cycling .. suggestions...
 

Peter wrote:
The system turns on (several existing problems have been repaired,
I think we're looking at the original problem) ....compressor
starts normallly and runs for a few minutes. When it's time to
cycle, compressor
keeps running, getting louder and louder (at which point I shut it
off). After waiting a period of time, the system can be started
again and the
process repeats itself. Starts normal and then runs on.

What do you mean by 'time to cycle'? Is the thermostat's call for
cooling satisfied?

A/C goes into "run away mode" instead of cycling .. suggestions...
 

On Fri, 04 Aug 2006 07:42:31 -0400, Peter wrote:


This is a two part Bryant Air Conditioner...24,000 btu. model number 513.. with a
through the wall compressor and coil. The second section is ceiling mounted air floor
distribution. Installed in 1994...R22 system. Has had regular preventative maintenance.

The system turns on (several existing problems have been repaired, I think we're looking
at the original problem) ....compressor
starts normallly and runs for a few minutes. When it's time to cycle, compressor
keeps running, getting louder and louder (at which point I shut it off). After
waiting a period of time, the system can be started again and the
process repeats itself. Starts normal and then runs on.

It does cool properly....and the fans are operable both in auto and cont mode.
This is a cooling only unit.... (not a heat pump)

Coils have been cleaned. A diagnosis was made about the flare connection
to the metering valve leaking like a "sieve", but I think this problem might have
been introduced into the system during diagnosis, as the freon level was measured
to be acceptable.

Any leads as to where the problem might be ???

Thanks in advance !!!

Peter

The compressor should have absolutely NO power applied when it is
'time to cycle'. Usually the 220 v power is removed by a
contactor(relay). The contactor is controlled by a 24 volt
thermostat line.

I suspect your diagnosis is wrong and it never reaches thermostat
shutoff. I suspect either a gross overcharge or burnt winding in your
compressor or both.


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