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Tried to replace my thermostat, made things worse...

I had an issue where my thermostat was no longer working so I went to replace it. I must've messed up the wiring because when I turned on the new thermostat, I noticed smoke coming out of whatever it is in the pictures I included below. This thermostat controls my basement heat which is water/baseboard gas heat. I disconnected the new thermostat and I think it would be best if I call a professional for this. Does anyone know what the below picture is? Would it be better to call an electrician or heating specialist?



Comments

  • Leon82
    Leon82 Member Posts: 684
    edited November 2017
    That's a switching relay with an internal transformer. Did the circuit breaker trip?

    Did you do any work on that box during the t stat change
  • steamsosteamy
    steamsosteamy Member Posts: 7
    Leon82 said:

    That's a switching relay with an internal transformer. Did the circuit breaker trip?



    Did you do any work on that box during the t stat change

    The circuit breaker did not break. Once I noticed the smoke I did kill the circuit breaker to remove the thermostat. I've never worked/touched that switching relay box.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    edited November 2017
    Call a heating professional. You may need a new relay, t-stat or both. Most electricians aren't going to know what they are looking at.



    steve
  • ratio
    ratio Member Posts: 3,616
    You need a competent heating professional. While you might be able to find an electrician to work on it, it's part of your HVAC system. Try the blue bar above, "Find a contractor", or tell us where you're located.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Sad but true, most electricians don't know controls.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • ratio
    ratio Member Posts: 3,616
    As a washed up electrician, I have to say that controls are not an electrician's responsibility. While many electricians could figure it out (given time), a boiler technician should recognize the function of the controls nearly immediately, if not the particular brand/model number off the device.

    TL;DR: call an HVAC technician experienced with the style heat you have for trouble with anything attached to it

  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    edited November 2017
    When you have someone come out, point this out to them, as well as the toasted coil in the relay above it.
    steve
  • steamsosteamy
    steamsosteamy Member Posts: 7
    edited November 2017

    When you have someone come out, point this out to them, as well as the toasted coil in the relay above it.

    Thanks, will do. Would that coil be part of the relay box?

    Edit: What is that thing you circled in the image?
  • Leon82
    Leon82 Member Posts: 684
    That's a neutral wire that has seen better days. There should be a plastic nut on the end of that connector so the wires don't touch the metal.

    I didn't even notice the coil on top, its done
    Canucker
  • JUGHNE
    JUGHNE Member Posts: 11,042
    You changed your wall T-stat? Was there only 2 wires coming out of the wall? If so you could most likely not screw anything up with just those 2 wires.

    The picture with the circled wires......by code no bushing is required on the male threads above the locknut.
    That scarring of insulation is a result of bad installation.
    That is probably MC cable with solid wire.

    IMO the best wiring for boiler controls/power is stranded #14 in 3/8" flex conduit. Takes longer but you are not having solid # 12 copper wire putting stress on terminals.
    Solid_Fuel_Man
  • HVACNUT
    HVACNUT Member Posts: 5,804
    Its possible the 845 was the problem to begin with. Agree with all from above. Get a heating pro. He might even recommend bringing all the zones into one, multi zone control board.
    Solid_Fuel_Man
  • steamsosteamy
    steamsosteamy Member Posts: 7
    JUGHNE said:

    You changed your wall T-stat? Was there only 2 wires coming out of the wall? If so you could most likely not screw anything up with just those 2 wires.

    4 wires, 2 were capped as my prior T-stat was only using 2. The older T-Stat was battery powered (batteries were replaced before realizing it no longer worked).