timer thermostat?

[Mainiac Mat]

Hey gang,

I have a 60K BTU HotDawg in my 26x30 detached garage.

If I heat the garage to ~60* in the evening and then shut the heater off, the garage is well enough insulated that I usually won't go below freezing that night. So I'd like to be able to come home from work and run the heater for an hour or so, and not have to worry about remembering to go out an shut it off.

Does anyone out there have any experience using a 24 v thermostat with a built in timer? Does such a critter even exist? Something simple that doesn't require programming for the entire week?

 

[The Metric System]

In the case you describe I would use a conventional 24-hour timer relay to make/break power to the existing thermostat or the go signal between the existing thermostat and the heater.

 

[fitter30]

Have internet in garage? Alexa relay? Setback thermostat can run on 3 AAA batteries or three wires R,W,C.

https://www.amazon.com/Programmable-Thermostat-House-Display-Backlight/dp/B0FHPR3MP1/?tag=atomicindus08-20

 

[Mainiac Mat]

Have internet in garage? Alexa relay?

We get decent WiFi in the garage (I can stream music).

Dummy me just wants an egg timer so I don't have to think about this.

We have a ring cam / alarm system. We do not have Alexa (I was gifted an echo dot years ago and never plugged it in) as I don't want big brother listening in on my conversations.

That said, app control would be nice.

 

[Bert_]

You can put a plain old spring wound timer in series with the thermostat. Most are intended for 120v, so I'm not sure if the contacts would stay clean switching 24v. Cheap enough to just try and find out

 

[JohnX14]

Any $40 programmable thermostat will do what you want this to do. The setup can't take 5 minutes. Why re-invent the wheel?

Personally, I'd turn the heater up when I walked in, and down when I left. Same as the lights. (actually I have an occ sensor for the lights.)

 

[larry4406]

Don’t some of these heaters need to have the fan run to safely cool the heat exchanger down?

Wouldn’t abrupt termination of power possibly affect this cool down thereby damaging the heat exchanger?

 

[JohnX14]

Don’t some of these heaters need to have the fan run to safely cool the heat exchanger down?

Wouldn’t abrupt termination of power possibly affect this cool down thereby damaging the heat exchanger?

I don't think he wants to kill the 120V, just the 24v t-stat signal. But I don't think there is a post-purge on the hot dawg heaters. And I have 2 of them. I need to pay closer attention.

 

[Mainiac Mat]

Don’t some of these heaters need to have the fan run to safely cool the heat exchanger down?

Wouldn’t abrupt termination of power possibly affect this cool down thereby damaging the heat exchanger?

yes and possibly

 

[The Metric System]

yes and possibly

Is the run-on function controlled by the thermostat, or internal to the heater?

If it's internal to the heater you could shut down the T-stat (or break it's go signal circuit) and the heater will respond the same way it does to the normal end of the cycle when the controller satisfies on temperature.

 

[Mainiac Mat]

Is the run-on function controlled by the thermostat, or internal to the heater?

internal to the heater

 

[fitter30]

Put the echo in the garage put it on a switch operating a relay n. c. and let the mice talk to it. Entering turn power off to it. Looking for freeze protection thermostat across terminals of relay.