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Nest and 1950s Arcoliner Furnace

Cloudbrk
Cloudbrk Member Posts: 1
in Thermostats and Controls
Hello all! I am hoping that someone here might be able to help me out.

I have a home with a 1950s Arcoliner Furnace/Boiler and I am wanting to hook up a smart thermostat to it. I purchased a Nest thermostat, but am having trouble getting it to work. The current thermostat has a R and W wire (non stranded) going to it. I hooked those up along with a C wire conversion kit (24v plugged into the wall). Nothing happens at all when I flip the breaker back on.

I followed the thermostat wires back to the control box (pictured below) and see that it is marked 120v. Is this system compatible with Nest or am I in the small percentage of systems that this will not work with. If so, is there a different relay/transformer setup that I can install to make this work?

Comments

  • pecmsg
    pecmsg Member Posts: 5,353
    Why is it always a NEST? o:)
    mattmia2realliveplumberMikeAmann
  • Ironman
    Ironman Member Posts: 7,570
    That old relay probably doesn’t have a common terminal available. However, I’d recommend that you ditch the Nest, it’s the worst possible thermostat for a hydronic system.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • gyrfalcon
    gyrfalcon Member Posts: 179
    eBay.  T87 Honeywell . Silent and reliable. 
    Slant Fin Galaxy GG100(1986) , 2 zone hot water baseboard, T87 Honeywell thermostats. 
    pecmsg
  • pecmsg
    pecmsg Member Posts: 5,353
    edited January 6
    https://www.pmmag.com/articles/104820-dan-holohan-do-you-miss-the-t87
    Thanks @DanHolohan

  • HVACNUT
    HVACNUT Member Posts: 6,382
    I'm not familiar with the plug in Common thing.
    Try switching R and W at the thermostat.

    I don't like the line volt wires coming into the relay without connectors.
  • mattmia2
    mattmia2 Member Posts: 11,042
    Where is the wall wart connected? The nest power connector only shows getting power from the equipment power transformer and doesn't isolate the 2.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,606
    edited January 6
    Want it to work 100%??

    Add a transformer and a relay. See attached. Connect orange & yellow from the new rib relay to the two thermostat terminal's on your old relay T & T
  • pecmsg
    pecmsg Member Posts: 5,353
    EBEBRATT-Ed said:
    Want it to work 100%?? Add a transformer and a relay. See attached. Connect ORange & Blue from the new rib relay to the two thermostat terminal's on your old relay T & T
    No attachment. 
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,606
    It's there now
    pecmsg

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