Dan wrote:
As a second option, maybe I
could connect a wall mount thermostat of the type used on a central air
unit, which would be more accurate. Does anyone know if this can be
done? I'm guessing the thermostat on a window unit directly turns the
compressor on and off, and therefore has the current switching capacity
required for this, while a wall mount type for a central unit probably
signals a central control board on the furnace/ac, which has a relay
that does the actual switching. Is this the case? I could probably set
up a relay, still we're beginning to get to the point of a lot a
screwing around by that time. Anyone have any ideas?

I also have an LG air conditioner with digital controls and would like
to do the same. Mine is a rather large and expensive unit, so I am
reluctant to butcher it or risk damaging it. I am curious as to what
type of component the temperature sensor is.

If the temperature sensor for the digital controls is a thermistor
then it would be easy to make a circuit involving a central AC
thermostat (you would need a stat that uses a relay output instead of a
triac) and a couple of resistors to emulate the sensor indicating a
high temperature or a low temperature to manually control the
compressor.

If the sensor is some sort of temperature sensitive transistor, it
would be a bit tougher to design a similar circuit. If it's a
thermocouple, it is even worse.

If you were to do something like this you would have to beware of
evaporator coil freeze up, especially at the temperature you wish to
run the unit at, since the temperature sensor is no longer in front of
the coil. Evaporator coil freezup can easily ruin the compressor.

Eric