Timer / Temperature based switch for Rheostat

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New Member
Feb 11, 2021
Menomonie, WI
Good morning,

After searching far and wide I thought I'd sign up and ask the experts here...

Last year we had an RSF Opel 3 put in on new construction. The stove has been working great though I'm still learning the ins and outs of it.

During the day it's enough to effectively heat the entire house. The night time is where I'm having issues. It's been roughly -10F the past week. I can load the stove up at night and have a nice bed of coals the next morning.

The problem comes with the two blowers. The internal blower works great, especially because it is controlled by the stove temperature. The central blower is all manual. Without the blowers running the whole room basically overheats as I have no way to move the air around otherwise. The internal blower doesn't help as it just circulates air around the room. (Helps cool off the stove I'd wager though) If I leave the central blower on overnight, the whole room becomes chilly by morning and is now blowing effectively cold air around the house.

What I think I need is either a thermostatically controlled rheostat or a timer controlled rheostat. Something that I can set to have the central blower turn on/off overnight. The blower is in the basement so basically the switch would be sensing room temperature dropping (and turning off) or raising (and turning on). The timer would be a set it and forget it method (off in X hours).

I couldn't find any good answer from the google gods. Does something like this exist? About the only thing I did find was that you don't want to use a light based dimmer on a fan because the two operate differently even though they look the same...

Thank you!


Staff member
Nov 18, 2005
South Puget Sound, WA
Sounds like a cooling thermostat controlling the second blower would do the job. Think of the second blower as AC cooling down the room. Set it for whatever comfort level is desired in the fireplace room, say 74º, so that the second blower comes on when the room temp exceeds 74º. For best operation, place this thermostat in a location that is not directly affected by the radiant heat or the primary fireplace blower.