I have to replace yet another humidifier. I ran across this thread discussing how a window a/c unit can be made into a more reliable dehumidfier. I have a Panasonic CW-121VS12L6U sitting in my basement that would work great for this. I can wire a house but I do not have much experience with humidistats and circuit boards. Can someone give me guidance which humidistat I should purchase and how to wire it in replace of the t-stat?

 

This is where knowing where you are in the world would help. AC power and power requirements.

If the AC currently works, here are a lot of these sorts https://www.ebay.com/i/322296759644?chn=ps&dispItem=1 of things on ebay. This one has an Austrailian plug. They are sold with heating and dehumidifying outlets too.

So, there are no potential modifications required as long as you can pull the plug, the AC turns off and turn it on again and it continues your fine.

So, set AC to minimum cool, set desired humidity, plug into outlet and go.

There is one potential issue, but it's usually not a problem with small air conditioners. Turning on and AC under load (e.g. just turns off) creates a large surge current. Short cycle timers prevent that. Smarts in the controller prevent that.

 

This is perfect, Thank you!
(I am in the Midwest, USA)

 

So, this http://www.ebay.com/itm/Digital-Hum...UG-/322296726692?_trksid=p2385738.m2548.l4275 one works for the US market.

The only real question which may not matter is, what happens when power fails?

This is the same question I asked you about the AC.