Thermostat bipass relay

[TboneMan]

I've had a direct vent CB1200 for three seasons now. I have it connected to a UPS so should there be a loss of AC power, the house won't smoke up (happened once prior to purchasing the UPS).

Obviously the UPS can only sustain the stove for a finite period of time. I was thinking it would be nice if a loss of main power occurred, that the thermostat (battery operated), would turn off to guarantee that the UPS has sufficient juice to cycle the stove down.


Here's my thought. It just so happens the thermostat wire runs very close to my house's hard wired door bell transformer. I'm thinking of powering a low voltage relay with the door bell transformer that would kill the thermostat call signal when AC power is loss to the transformer.

Anyone do anything this crazy before? Or have I been watching too many Mythbuster episodes.

 

[tjnamtiw]

Actually, that's a helluva good idea! Put the thermostat's battery also on a set of N.C. contacts so, when the relay drops out, the battery voltage powers a small piezo alarm to let you know power is out.

 

[TboneMan]

Actually the UPS will begin beeping when AC power is off, so I'll know that if I'm home (say, in the middle of the night). I'm thinking of it as more piece of mind when the stove is on and I'm not home.

Plus, if the power is off for a couple of hours while I'm not home and is then restored, the stove will restart and begin heating the house back up.