I am trying to install a google nest thermostat in my old milwaukee thermoflo furnace; model 1203-B10. I do not have a current C WIRE hooked up at the thermostat. There are 3 wires run to the thermostat, but only 2 are used. Could it be as simple as connecting the unused wire to the TR spot? Would this make it a "c wire" that I could hook up the spot for the C wire on my nest?
Last edited by PJmax; 12-06-22 at 06:45 PM.
Reason: resized pics
red, white, and blue run to the thermostat. The White is hooked up to the TH spot. The red goes to a wire nut that is connected to a load wire. The blue is unused
Hello!
Like many others, I am looking to replace my old thermostat with a smart thermostat. I have reviewed several threads others have had regarding this issue, but couldn't find anything to specific to my exact setup. I will admit that I am not super knowledgeable when it comes to heating and electrical, so am hoping someone with expertise in this area can help me understand what the issue is and how to fix it.
I have a Burnham boiler that provides heat. No air conditioners or heat pumps. I have an Aquastat Relay Type L8124A with three Taco 571-2 valves and a thermostat for each zone.
I am looking to replace one of my old Honeywell round thermostat with an Amazon Smart Thermostat. Would like to potentially upgrade the other two at some point, but want to troubleshoot this first one before doing so.
When I removed the old Honeywell thermostat, there were only 2 wires connected to it: Red and White. In the brown wire that included the red and white wires, I did find an unused blue wire.
When I connected the red wire to the R slot, the white wire to the W slot, and then the blue wire to the C slot, the new thermostat did not power on. From reading other threads on this topic, it sounds like the way the wiring is setup is backwards or not setup to support the C wire.
Question is why is the thermostat not powering on? Am I able to use the unused blue wire as the C wire? If so, how can it be done?
Here are some pictures of my current setup. If there is additional information or pictures needed to help with troubleshooting the issue, please let me know. Again, not very savvy when it comes to this sort of stuff, so will greatly appreciate any help I can get. Thanks in advance!
[img]https://cimg5.ibsrv.net/gimg/www.doityourselft.com-vbulletin/585x969/ice1_dd6b190e9d656aabe5e85ea2b117b0196118c962.jpeg[/img]
[img]https://cimg6.ibsrv.net/gimg/www.doityourselft.com-vbulletin/571x429/ice2_fd6bccf8309ade02a1bb60d23e34de30c58bbe6b.jpeg[/img]
[img]https://cimg7.ibsrv.net/gimg/www.doityourselft.com-vbulletin/808x407/ice3_fba86604062dd76ea8d97dcfe93d7e35d52a076a.jpeg[/img]
I would like to install 2 nest T-stats to my 2 zone heat only system.I have an oil boiler with a TacoSR503 3 zone switching relay.I ran all new 6 wire to both thermostats.Is there a terminal I can hook into inside the taco unit for c wire or should I just hook up new transformers with separate plugs of each t-stat?
12-06-22, 06:30 PM
