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How to SAFELY hide ugly fan control relay

Motorapido
Motorapido Member Posts: 307
I need to surface mount a junction box on the side of my Empire freestanding gas hot air heater/furnace, with a fan control center relay sitting on top of the metal box cover. This is in a vacation rental cottage I just bought. I'd like to hide the ugly metal box and the ugly fan control center relay that sits on top of the box, but I want to do it safely. I assume they mount these fan controls on top of a box cover plate to aid in heat dissipation from the 24v transformer. I'm looking for a small metal box that I could mount to cover the box with the relay/transformer, and preferably a cover that has slots cut in it for air circulation. Many have probably encountered this same situation, so I'm guessing there is a hide-the-ugly-transformer solution out there that would be safe and not trap heat inside. Any suggestions?

Comments

  • pecmsg
    pecmsg Member Posts: 4,776
    Is this a Vent Free Heater?

    Why do you need a Fan Control?
  • Alan Welch
    Alan Welch Member Posts: 266
    Mount it on the inside 
    SuperTech
  • Motorapido
    Motorapido Member Posts: 307
    It vents through the wall. Long story on the fan control center. This is a millivolt gas valve heater. I'm adding a wifi thermostat as the primary stat with the millivolt thermostat as the backup when power goes out (property is deep in the middle of nowhere in the unexplored woods, where power outages are frequent). The fan control will give me 24v power to the Honeywell wifi thermostat and the relay will then make the millivolt contact. I know I can't bury the box with the fan control inside a wall. Surface mounting on the side of the Empire heater seems like the logical location, and I want to hide the ugly fan control and also protect if from idiots who rent the property and might take it upon themselves to poke at the fan control with a kitchen knife. Renters do dumb stuff.
  • PC7060
    PC7060 Member Posts: 1,155
    edited February 2021
    That relay is design to face mount to a 4" electrical box; available from Home Depot Lowes, etc.

    Since this may leave connections exposed, I'd add a 4" extension ring to do the connections and bring the wires out through the side punch out using strain relief. Be sure to separate low voltage control from 110V input.

    Edit: Is the reverse side designed to be exposed? No exposed electrical connections? If so then you wouldn't need the ring.
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    Show a pic of the equipment.
    steve
  • Motorapido
    Motorapido Member Posts: 307

    Show a pic of the equipment.

    Picture of the gas heater/furnace? (This is from the manufacturer catalog, but it's what mine looks like). I planned to attach the box with the fan control onto one of the two side panels. The fan control should sit on a proper, enclosed junction box, since the mains voltage attaches at the bottom, which would be inside the box. I just want to cover the entire box so it's not exposed in the room, but without causing overheating of that is a consideration on this type of transformer.


  • PC7060
    PC7060 Member Posts: 1,155
    edited February 2021

    Mount it on the inside 

    As @Alan Welch said, I'd put it inside the cabinet somewhere
    SuperTech
  • Motorapido
    Motorapido Member Posts: 307
    Maybe a vented box surround-cover like this??
  • Ironman
    Ironman Member Posts: 7,367
    How about on the back of the unit, away from the flue pipe?
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Ironman
    Ironman Member Posts: 7,367
    As a side note: that relay makes a loud "click" which may be objectionable to someone who's sleeping near it.

    Also: if power goes out, your not gonna have wifi.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • PC7060
    PC7060 Member Posts: 1,155
    edited February 2021
    The

    Maybe a vented box surround-cover like this??

    That unit is overkill. No need for venting, the 4" box are fine. Did you figure out if the reverse side of relay from picture is designed to be exposed?
  • pecmsg
    pecmsg Member Posts: 4,776
    PC7060 said:

    The

    Maybe a vented box surround-cover like this??

    That unit is overkill. No need for venting, the 4" box are fine. Did you figure out if the reverse side of relay from picture is designed to be exposed?
    Thats a fan center. Honeywell's module relay plugs into it. Only the 24 volt is exposed!
    PC7060mattmia2SuperTech
  • Motorapido
    Motorapido Member Posts: 307
    Ironman said:

    As a side note: that relay makes a loud "click" which may be objectionable to someone who's sleeping near it.

    Also: if power goes out, your not gonna have wifi.

    I can live with the click. I'll wire the millivolt stat in parallel with the wifi stat. I will set the millivolt stat to 55 or 60 degrees. If wifi and or power goes out, the Honeywell wifi stat will not work, but the millivolt stat will still work, preventing burst pipes. My plan is to put a thermostat lock box over the millivolt stat so renters cannot tinker with it, since that will be my no-pipe-freeze safety if power is off and the wifi thermostat is rendered non-functional.
  • Motorapido
    Motorapido Member Posts: 307
    PC7060 said:

    The

    Maybe a vented box surround-cover like this??

    That unit is overkill. No need for venting, the 4" box are fine. Did you figure out if the reverse side of relay from picture is designed to be exposed?
    Dunno. When mounted on the 4 inch box, the 120v connections will be inside the box. The 24v stuff sits up on top of the box. That 24v top stuff is what I want to cover and protect. Here is a pic.

  • Ironman
    Ironman Member Posts: 7,367
    Why don't you put a thermostat lock box over the fan center?
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Motorapido
  • pecmsg
    pecmsg Member Posts: 4,776
    This is really getting more complicated than it has to be!
    mattmia2SuperTech
  • mattmia2
    mattmia2 Member Posts: 9,575
    you can put a 24v transformer at some other convenient location and just run the t-stat wire to the console heater or to the t-stat or splice it at some place between the to to the thermostat wire.
    Motorapido
  • mattmia2
    mattmia2 Member Posts: 9,575
    You can get fixed thermostats that are just a little lump with 2wires sticking out set to anywhere from about 50 to 75 degrees which would be tamperproof. not sure if their contacts are rated for millivolt.
  • rick in Alaska
    rick in Alaska Member Posts: 1,457
    You might just want to find a really small 24 volt transformer, and get an RIB relay, and put them together yourself. That would take up very little room, and I am sure you could mount it behind the unit, and be very unobtrusive. As others have said, that fan control center is very noisy when the contacts close. I would not use it myself.
    Rick
    mattmia2SuperTechratioMotorapido
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,455
    I agree with mounting it remote and running wire to the heater if possible. A transformer and a rib relay might be easier to hide
    Motorapido
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,455
    Whoops. Didn't see @rick in Alaska post
  • JUGHNE
    JUGHNE Member Posts: 11,042
    I save a lot of the boxes that defrost timers come in as I just change the guts for replacement.
    I use these boxes to mount a variety of things in, usually contactors.
    You could put the small transformer inside and mount a RIB on one of the KO's.
    All wires inside the J-box and the RIB pilot light would be visible and impressive.
    I usually put nut and bolt thru the door latch.
    Motorapido
  • HVACNUT
    HVACNUT Member Posts: 5,804
    I don't know, a little paint, a few flowers, a couple of throw pillows, it'll blend right in. 
    Motorapido
  • Jamie Hall
    Jamie Hall Member Posts: 23,169
    edited February 2021
    If that wall furnace is anything like the Rinnai units I'm familiar with, there's ample space inside the case to put everything in there except -- obviously -- the two thermostats. Put the millivolt one somewhere nearby (keep the leads as short as possible) and the other wherever you want it.

    The Rinnais have a freeze protection mode which you might want to consider; a thermostat -- in this case, the millivolt thermostat -- is actually just inside the case of the unit where it is in the path of the intake air.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Motorapido