C Wire on Reznor Furnace.

[stangconv]

Want to do a Honeywell T5 Smart Thermostat in my Garage. I have a Reznor 75,000 btu forced air furnace. Anyone make this work?

 

[Milton Shaw]

Does it have a transformer. The two wires off the transformer furnish the 24 volts hot and neutral (C) for the control board and thermostat. Just tap off of them. If you do not have a transformer then you are probably out of luck as it's a low voltage thermo-couple system and does not provide voltage for a regular thermostat. Check the wiring diagram and go from there.

 

[stangconv]

Opened the unit, and there was a C wire inside. Made a jumper for it and we are rocking. Thanks

 

[Slowgsr]

Did it work properly? I had to add a 24v transformer to boost the current up as the transformer in the heater wasn't large enough

 

[LS6 Tommy]

Did it work properly? I had to add a 24v transformer to boost the current up as the transformer in the heater wasn't large enough

Why? A thermostat is not really any extra load...

Tommy

 

[Slowgsr]

Sure in theory. They have a battery in them that requires charging, they probably use more power then the electronics in the furnace.

My reznor 30kbtu wouldn't work properly it kept cycling, wouldn't stay on. YouTube it, lots of others had the same issues with the nest.

The idea seemed crazy, but after I added a 24v 30va transformer, the furnace has been working perfectly.

My schwank tube heater in my shop had a factory C connection, and working just fine with my nest.

 

[LS6 Tommy]

That's weird. The majority of the load a Xformer sees is the relays and gas valves, not the electronics. If upsizing fixed it, it obviously was the problem. Something new to keep in the back of my head.

Tommy

 

[stangconv]

Did it work properly? I had to add a 24v transformer to boost the current up as the transformer in the heater wasn't large enough

Works great on the Honeywell T5 Lyric. Been just beautiful. I tell Siri to get my garage ready and she warms it up for me.

 

[kppolich]

Works great on the Honeywell T5 Lyric. Been just beautiful. I tell Siri to get my garage ready and she warms it up for me.

I'll be doing this soon.

Did you just buy a molex connector and spade terminal for the jumper?
Can you share any pics?

 

[fitter30]

Never saw a reznor that didn't have a transformer. R to chassis should give you 24vac check with a meter

 

[PoorUB]

Never saw a reznor that didn't have a transformer. R to chassis should give you 24vac check with a meter

You need to go back about 60 years! There was some line voltage units out there back in the "olden days".

 

[4xdog]

I gotta do some checking! I'd love to have a wifi thermostat working on my detached shop's Reznor propane heater.