Wall Heater

Discussion in 'Electrical Forum discussion & Blog' started by Kiko, Oct 17, 2011.

  1. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    I am contemplating installing an electric wall heater in my lower bathroom. It shares a wall with my garage, and there happens to be a breaker box on the garage side of the wall, which services the garage and shop lights, etc. The specs for the heating unit is 120 volts and 1000 watts. Thus, it is pulling a little over 8 amps. My question is whether to run 14/2 with a 15 amp breaker or 12/2 with a 20 amp breaker. The 15 amp breaker makes sense, since there would be nothing else on this circuit, but for an electric heater, it seems the 12/2 and 20 amp should be used??
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,149
    Location:
    New England
    Normally, the installation instructions would specify the required breaker. But, given the 1000W, a 15A circuit sure seems like it should be more than sufficient.
  3. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    Thanks.
    I downloaded the instructions, but it just refers to "supply wires" without specifying what gauge they should be. And it doesn't mention a breaker size at all.
  4. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    Don't forget that it is to be figured as a continuous load per 424.3(B)

    14 @ 15 amp breaker sounds good to me
  5. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    Since the extra expense for this one small circuit would be minimal, you could gain a little "peace of mind" running 12 gauge. That would allow you to upgrade to a 1500 watt heater sometime if desired. But for a 1000 watt device, staying with a 15 amp breaker also give you the extra peace of mind in case of a fault inside the unit sometime....breaker will pop sooner!
  6. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    Thanks all!!
    Jimbo makes a compelling argument, which I was wrestling with myself. But this 1/2 bath is so small that upgrading to a 1500 or 2000 watt heater won't be necessary. I also think it would be better to have the breaker pop at 15 amps than 20 in case of internal fault.

    Speaking of "faults", I read somewhere that these heater circuits in a bathroom must be GFI protected. Is that really a code?
  7. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    If it cord and plug connects yes but otherwise no
    Good idea? It would be up to you but I wouldn’t
  8. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    I started this project today and ran into a little unexpected glitch.
    The sub-panel I was working in is a Siemens, and the breakers are type QP.
    I was expecting to find separate neutral and ground busses, but instead there was a neutral bus and a single ground screw for all the circuits to share. There were already two ground wires under it (one of them was for a double-pole 30 amp breaker and one for a single-pole 15 amp breaker.) I had difficulty getting the third ground wire under this screw, but succeeded in the end.

    Why is there no long ground bus? And what are you supposed to do if you want to add additional circuits here? Do you just start pig-tailing the grounds together, so there is just one wire to go under that screw?
    Last edited: Oct 21, 2011
  9. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,540
    Location:
    North Carolina
    Buy a grounding terminal bus at the supply house and install it in the panel.

    Where does the equipment grounding conductor that was installed with the feeders land?
  10. leejosepho

    leejosepho DIY scratch-pad engineer

    I have used that kind of logic of my own in the past, like when suggesting an electrician install only 15A breakers on *all* circuits in an old house, and he did ... but then someone here offered some kind of reason for saying the desired effect of "extra protection" might not actually happen there (but now I forget what that reasoning actually was). And then related to all of that, I am sometimes surprised to see old 12ga wire that looks to me like 10ga, and then to see new 12ga today that looks to me like 14ga. So, I now just typically use a breaker that matches whatever it written on a given wire's insulation and hope all will be well as long as both are properly rated for the actual load.
  11. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,837
    Location:
    Cave Creek, Arizona
    Circuit breakers are sized to protect the wires, NOT the appliance, so if it has #12 wire, it would be safe with a 20 amp breaker. In any case, the actual wire to, or inside, the heater will be MUCH smaller than the #14 you use with a 15 amp breaker, which means it COULD burn up before the circuit breaker tripped.
  12. ballvalve

    ballvalve General Engineering Contractor

    Messages:
    3,261
    Location:
    northfork, california
    A $39 oil fin heater sounds like the answer to me. Various heat settings, 1/4 the cost of a wall heater, and mine last about 6 years.Keeps your coffee cup warm too. Wall heaters die and usually the parts cost more than a new one that does not fit the hole.
  13. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    I suppose I'll have to buy that grounding bus if I install additional circuits.
    If you mean the large aluminum grounding wire, it is screwed to the panel under a similar grounding screw, just below the grounding screw for the circuits.
  14. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    Update:
    I installed the new circuit and the new heater with no further hitches.
    Unfortunately, the heater made a loud buzzing sound, which was unacceptable.
    I replaced the heater unit with a new one of the same make and model, and no buzzing.
    The manufacturer said the first unit must have been "dropped" during shipping.
Similar Threads: Wall Heater
Forum Title Date
Electrical Forum discussion & Blog Wiring in a 220 circuit for Tankless water heater - Cunduit from behind the wall? Nov 21, 2013
Electrical Forum discussion & Blog Wiring Multiple Wall Thermostat Controlled (Cadet) 240v Baseboard Heaters Apr 24, 2012
Electrical Forum discussion & Blog Noma fan forced wall heater 240v Mar 12, 2011
Electrical Forum discussion & Blog Wall Heater Wiring Aug 10, 2009
Electrical Forum discussion & Blog Vanity Wall Light - How Close to Ceiling? Jul 25, 2014

Share This Page