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Need 120 volt setback thermostat

If you've already got a pair of wires between each thermostat and the basement, then you can put your relay panels down there, and have a fraction of the 24V transformers you're picturing. Just disconnect the 120V source in each apartment. This is nowhere near as bad as doing a transformer and relay in each apartment. Take a look behind some of the thermostats. The stat's switching hot, and if you've also got a couple of neutral wires wire-nutted together in the box, you should be able to make this happen.


  • Dick Olsen
    Dick Olsen Member Posts: 7
    120 volt setback thermostat

    hard to find. Johnson and perhaps Honeywell say they don't have, as everyone uses 24 volt control. I need to spec for 200 unit apartment bldg, built in 1960s. 120 volt thermostat goes to basement to control 120 volt motorized control valve. Big energy savings for apartment owners if I can find one.
  • Empire_2
    Empire_2 Member Posts: 2,343
    WHy not

    Just use a lo volt set back stat, add a t-former and a relay?
  • John L.
    John L. Member Posts: 13
    Set back Tstat

    Honeywell makes a line volt setback.
    Put one on my Dad's electric baseboard.
    Not shure of the number.
    I will check and post later.
    John L.
  • Dick Olsen
    Dick Olsen Member Posts: 7

    too much hardware, must be mounted in each apartment unit, since voltage source is from the apartment panel.
  • superMARKet
    superMARKet Member Posts: 87
    Line volt setback

    120V or 240V?

    I thought that the only digital line volt thermostats Honeywell ever made were only rated for 240V.

    Manufacturers don't seem to realize that there are a ton of "electric baseboard" thermostats out there being used to switch circulators. Or maybe they do realize it, but they also know that line voltage thermostats tend to suck. I've never met one I liked, even digital.

    ****, I'd think seriously about ways to convert to 24V control. Do you have two wires between the thermostats and the valves now? Can you disconnect the independent 120V supplies easily?
  • Empire_2
    Empire_2 Member Posts: 2,343

    I think I know what you are trying to do, but just change to 24 (for each Apt) change the voltage going to the existing stats and you should be able to configure the basement valve after you are done. 120vac set back will probably cost more and add to the fact that they are a potential hazard to the customer. Just to be clear, you want set backs for each apt? to control (1) valve/pump or whatever?
  • oil-2-4-6-gas
    oil-2-4-6-gas Member Posts: 641

    if you want to save them Real money --install a Honeywell 3-way valve with outdoor reset or Heat-Timer 3-way valve with reset --keep the boiler/s at 180 if using for domestic --and only send up the temp necessary --we have had a dollar savings of 25% at 1 site

    ---what controls are in place now ?? i just re-read your post --do you know what you actually have in this complex? honestly,, you do not have a thermostat wire from each apartment going to the boiler room --that would be 200 sets of wire to the boiler room --umm NO -- if you have seperate thermostats they go to a zone valve in or near each apartment -maybe 30 averaging sensors --but this would be newer tecghnology-and a seperate outdoor stat -powering a pump/pumps cetraly located in the boiler room --any pics of this set-up ?
  • carol_3
    carol_3 Member Posts: 397

    Honeywell is supposed to have one coming, but I don't know when. I realize that doesn't help you much now. I'll see what I can find out,though.
  • Dick Olsen
    Dick Olsen Member Posts: 7

    120 volt thermostat source of power in apt, going down to motor valve in the basement. Valve opens when thermostat calls. Now two hundred of these individual circutis... Now you see the problem? Don't want to install 200 seperate transformers and relays in the apartment.
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