Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Modine/Thermostat Wiring

Greetings,



In my workshop, I installed a small ceiling mount Modine heater that is basically nothing more than a hot water coil with a fan. I have a 24V RIB relay that I'm using to control the 120V to the fan. I was planning on using a regular thermostat and connecting to the Green/Red/White terminals to control the zone valve for the unit and the fan. The problem I've found with my plan is the fan control in the thermostat(Auto/On) seems to only be designed to work when set to cooling mode, not heating. What is the best way to control this setup? I'm tempted to just connect the green and white wires together at the thermostat so the zone valve and fan turn on together. The only thing I don't like with that setup is I can't turn the fan on to just circulate air.



Thanks.



-Brent

Comments

  • Eric_32
    Eric_32 Member Posts: 267
    edited February 2012
    I've always..

    wired the 120v power to the fan to a service switch close by, then thru an aquastat either strap on or well type (like a Honeywell L6006C1018) on the outlet or return out of the coil. The tstat opens the zone valve which allows hot water to flow thru the coil, as the aquastat heats up the fan turns on.

    This setup keeps the fan from blowing cold air before the coil gets hot.

    You would have to lower the aquastat way down to turn the fan on during the summer for cooling, and control it with the service switch, but it may work.
  • Wesman
    Wesman Member Posts: 16
    Fan control

    The advantage with above response is correct, you dont blow cold air on an inital  call for heat.



     Are you able to program the tstat for "electric heat"?  In this mode both the W1 and G would energize on a call for heat.
  • Wesman
    Wesman Member Posts: 16
    Fan control

    The advantage with above response is correct, you dont blow cold air on an inital  call for heat.



     Are you able to program the tstat for "electric heat"?  In this mode both the W1 and G would energize on a call for heat.
  • billtwocase
    billtwocase Member Posts: 2,385
    wiring

    Eric is correct. I prefer the control, well mounted into a "T" on the the supply, which is on the bottom. You can run a separate power source to the blower motor. I would have an electrician do that for you
  • Brent H.
    Brent H. Member Posts: 161
    Thanks

    Gentlemen,



    Thanks for the ideas. I was able to set the thermostat to electric and then change another setting and it is now turning on and off with the heat. Eventually I may put an aquastat on it but for now it'll work fine. It's only used on occassion when I want to take the chill off in the shop.

    Thanks again.



    -Brent
This discussion has been closed.