Thermostat replacement

[daverave]

We were down in NM in March and wow it’s cold there! Anyway when it’s in the low teens at night we don’t like how often the heater goes on and off so we’d like to replace the FWC Emerson thermostat with one that has a set point lower than 45*. There is a Honeywell “garage” model that can be set at 35* which would be an improvement.
The original thermostat wires are large gauge and were quite difficult to get on the much smaller Honeywell terminals. I’m not sure why they were that gauge… maybe because of the 12 volt power?
Plus the wiring for the original includes a smaller gauge connection that the new one doesn’t have.
See photos in next post for the original and new thermostat wiring. Before I burn down our camper, any opinions on whether this is going to work?

 

[daverave]

We were down in NM in March and wow it’s cold there! Anyway when it’s in the low teens at night we don’t like how often the heater goes on and off so we’d like to replace the FWC Emerson thermostat with one that has a set point lower than 45*. There is a Honeywell “garage” model that can be set at 35* which would be an improvement.
The original thermostat wires are large gauge and were quite difficult to get on the much smaller Honeywell terminals. I’m not sure why they were that gauge… maybe because of the 12 volt power?
Plus the wiring for the original includes a smaller gauge connection that the new one doesn’t have.
See photos in next post for the original and new thermostat wiring. Before I burn down our camper, any opinions on whether this is going to work?

 

[daverave]

IMG_1225.JPG

 

[daverave]

Note that the original thermostat wiring had the white wire going to the “RC” terminal while the new one is on the “R” terminal.

 

[rubberlegs]

Hmmm... I did the same thing, probably the same thermostat. But I don't recall any issues with the wire gauge. It's nice being able to set the temperature above freezing, but not have it on all night.

 

[daverave]

Note also that the new thermostat is old-school manual while the FWC original is digital. I'm unsure whether that explains the differences in the wiring.

 

[UmkaAndHawk]

Well, no issues here, doing virtually the same thing. Also, it's pretty great being able to set the thermostat above freezing, but not coming on all the time. I kinda think this should be standard; folks (like me) who are unaware of these garage thermostats are suffering with frozen pipes or with a furnace that goes on all the time.

 

[daverave]

So did you replace your thermostat UmkaHawk?

 

[ckent323]

I replaced our original thermostat several years ago with a Honeywell manual garage thermostat having a low temp setting of 35 Deg F and which can be mounted horizontally making it easy to access the lever to turn it off and on from the over cab bed.

Works perfect.

 

[Old Crow]

Page 2 of the manual for the CT50K 1028 says:

"For CT50/CT53/CT54: If your old thermostat has 3 or more wires (not counting terminals C or C1), you may have purchased the wrong replacement thermostat. Stop now and call 1-800-468-1502 for advice."

I don't think that red jumper would be considered a third wire but I'd call the number and ask whether it's needed on the CT50K for your furnace.

Link to the User Manual (at the bottom of an Amazon listing for a CT50K)

 

[daverave]

Thanks for everyone's input. It worked just fine, so far.
Now we're off for several days to explore central Nevada where the furnace and thermostat should get a decent work out.
Dave