retrofit old air conditioner's thermostat?

[david]

I have an old air conditioner that uses non electronic temperature control. It exhibits a large hysterisis. In other words, there is a large temperature difference between when the pump kicks in, and when it turns off. This means the air con won't cycle off until it's way too cold, and if I adjust the thermostat to fix this, then it won't cycle on until it's way too hot.

Is there a commercial product to retrofit this type of thermostat with an electronic one? This could be done by wrapping a heating coil on the temperature probe of the old thermostat. Then when it is desirable to cycle on the air cond, just heat the coil a little, and when it is desirable to cycle off the air cond, just turn off the heating coil.

[hrhofmann]

If you are going to go to all that trouble, then why can't you just turn the ac temp knob to turn it on, and then back it off? You could also take the temp control off the unit and see if you can improve its reponse by locating it more in the airstream so it responds quicker to a drop in temperature.

[DT]

I converted a large window unit and it worked flawlessly. I just bought a line voltage temperature controller with remote thermocouple and plugged the AC unit into it. Leave the temperature knob turned all the way down.

I used a Love controller from Dwyer, I think this is the series I used:

You could do it with a cheaper controller (available at Home Depot) but the Love is adjustable for span and has a remote so you can sample air temperature away from the unit. I have never had a room temperature so nicely controlled.

[FatterDumber& Happier Moe]

I wired a transformer/relay/room thermostat to an outlet for the window AC. Works great.

[hrhofmann]

THis is a much better solution than spending $89.00 for the Love controller.