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On Mon, 17 Jul 2006 12:39:10 -0400, wrote:

Now if I can figure out how to keep my A/C from cycling so much, I'll
be in good shape!!

Is the unit oversized? That is the first suspect in short cycling.
If it is sized right you can try more insulation, location of the
thermostat or better air flow. Is it creating one small cool spot near
the thermostat. That will cause short cycling. As the air spreads out
it calls for cooling again. A fan might help. If the whole area is
heating up quickly you need to reduce the heat load (insulation,
window covering etc). That will also save money. I assume this is a
boat so it is probably going to be hard to

It's a 12,000 BTU unit on a 30' Sea Ray, so I think it's sized
properly. It's the same BTU as the old unit, but the old unit seemed
to bring the temperature of the boat down faster.

During the day, it runs almost constantly, so under high heat load, it
works overtime bringing the cabin temperature down. The heat load is
pretty horrendous on these boats, especially here in Florida.

I went from the tried and true copper tube thermostat to a new digital
thermostat when I installed the new A/C, and I think the old
technology is more fitting for a boat, because I did not have cycling
problems with the old A/C system.

The problem is, the A/C will bring the cabin down to temperature, but
the temperature rises so quickly after the A/C cycles off, that it
cycles right back on again. I bought and installed the optional
remote temperature sensor, which I mounted in the return air duct, and
this helped a little bit, but did not cure the problem.

My next experiment will be to see if I can set the system so the fan
runs continuously, and does not cycle off with the compressor. I'm
thinking this may keep the air "mixed" better. I have two small fans
in the cabin, but they sound like a P-51 Mustang at takeoff, so
they're not something you can run at night!