Use an AC unit for cold storage.

[riverdan]

In a well insulated room I would like to use a small air conditioner to bring the temp down to about 33 to 40 deg by heating the thermostat to get below the normal 60 deg. with one sensor then defrost it with another sensor when it begins to frost over. I would like to have two set points with a led display, the room temp and defrost temp. I have started with a Pic16f886, however I am not a very good programmer. I need it to store veg's from my garden. I sure could use the help, i am OK with building the PCB.

Thanks Everyone

[texasclodhopper]

I believe you will find out that you will reach a point where the A/C will cool the room no further. It isn't a function of the thermostat. It is a thermodynamic function.

Most that I know will cool 20 or 25 degrees cooler than the outside temperature.