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Community and Q&A

Best type of backup electric heater?

Kail_Z | Posted in Energy Efficiency and Durability on

I am building a house in climate zone C4 and installing a two headed ductless heat pump for the primary heat source. The house should be very air tight and have around R28 walls when finished. I want to put some sort of backup electric heaters in the bedrooms to make sure they stay comfortable if the doors are closed.

Do you guys have any recommendations for back up electric wall heaters? I have used Kings in the past and they seem like a quality product and reasonably priced, but I would like to hear what you guys are using. Price, efficiency, and cosmetics are all factors.

I am assuming that the smallest wattage I can find will heat the rooms but would like to hear your feedback on this as well.

Thanks for the help

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  1. brp_nh | | #1

    We have 500 watt Stiebel Eltron wall heaters in our bedrooms:

    They look good and are a bit over $100, but are 240v and have an imprecise knob to set temperature.

    In hindsight, I'd spend the extra money for the 500 watt and 120v plug in Convectair Apero:

    Mostly because they have a digital thermostat and are 120v plug in.

  2. Yamayagi1 | | #2

    Comfort Cove radiant wall heaters. Or plain old (hardwired) baseboard electric if it fits into the room layout.

  3. STEPHEN SHEEHY | | #3

    I'd get cheap plug in heaters until i find out if I really need any supplemental heat. If the house is well insulated and airtight, leaving the bedroom doors open most of the day may be enough to keep them warm at night when the doors are closed. If you end up needing something nicer, the Convectair is pretty attractive and quiet.

  4. SwitchgrassFarmer | | #4

    I have a QMark Smart Series wall heater on the ground floor of our house. 1800 - 4000 watt range, probably too big and ugly for a bedroom.

    Having such a heater came up in our home insurance review. The insurance carrier wanted to know that we had some sort of hard wired backup that could run in the event we were on a mid-winter Caribbean cruise, our geothermal HVAC system were to fail, and we weren't on site to have a fire in the masonry heater. (The fact that we just built a new home and have no money for a cruise didn't eliminate the requirement.)

    Neat thing about the QMark was how it mounted into the wall, and that it had a building automation interface capability so we could interlock it with our HVAC controls if we should so desire. It was also a unit that our electrician had past good experience with.

    My assumption is that combined with the energy efficiency of the house, passive solar gain, etc, that the QMark would keep the house from freezing. I must admit that I didn't do any sort of detailed calcs to verify that though.

    The key thing is that I am superstitious; now that I spent the money to buy and install this backup heater we will likely never need it.

  5. STEPHEN SHEEHY | | #5

    Andrew- we had to change insurance carriers because our original insurer wouldn't cover a house without something to provide heat in addition to our two mini-splits. Apparently, someone determined that in Maine it is impossible to keep a house warm with heat pumps. I was tempted to send a photo of our indoor/outdoor thermometer showing -8 F outside and 68 F inside, with just one of the mini-splits turned on.

    A vent-less propane heater? No problem? Kerosene heater? No problem. Wood stove? No problem. Electric resistance heater? No problem. But two Fujitsu mini-splits? Sorry, too much risk.

  6. SwitchgrassFarmer | | #6

    Picture of the QMark heater, with a cat for scale.

    Stephen, I had read somewhere that there might be an insurance company expectation of backup heat source for "alternative" HVAC systems, so we put in the QMark at the start. Of course we wouldn't want the water in the PEX in our floors to freeze anyhow.

    I went back and looked at the original questionnaire to see how it was phrased: "Do you have a secondary source of heat?". Right under: "Do you have an oil tank..." (We don't have a trampoline or swimming pool either.)

  7. Expert Member

    No money in the budget for a cruise? That shows a disturbing lack of forethought. Around here spec builders call their first mortgage draw the "pickup truck draw". Once they have their shiny new F350 then they can worry about how to complete the project.

  8. SwitchgrassFarmer | | #8

    Yea Malcolm, I really did mess up there. Could have done the cruise thing versus the new house. Unfortunately, given my personality, I probably would have attempted it alone in some grand fashion, and likely ended up like that poor German sailor that was just found mummified drifting off the Philippines.

  9. user-626934 | | #9

    Under $100 each. Available as "small" as 500W. A bit noisy...but based your post, you probably won't need to use them much, if at all.

  10. bobhol | | #10

    In Peterborough Ontario ,we recently went through a weekend cold spell with temperatures of -35 F and the 2 Fujitsu mini splits kept up fine( one on each floor) with 115 F heat output as measured at the head unit first thing in the morning and room temperature of 72F aux baseboard heaters have never been needed and we rarely ever get that cold ...but...I was told the baseboards were required by code

  11. GBA Editor
    Martin Holladay | | #11

    That's impressive. Thanks.

  12. Kail_Z | | #12

    Thanks for the info everyone. I don't think I need the heaters by code, but there are some incentives that I would like to receive from our power company that require a back up heat source. I am interested in the cove heaters and noticed that King also makes a economical version. Have people had good experiences with cove heaters? I haven't seen one installed before.

  13. BillDietze | | #13

    If you search this site for "Cove heater", you'll get a bunch of good information.

  14. bobhol | | #14

    Hi Martin....Fujitsu H series ....they were working for sure but they were fine for the 2 days we had the arctic air blast ....My Generac didn't work as normal though...we had a power outage at 10 pm and the generator didnt start. I got it going after a few minutes of manual start procedure ,but that is another story...

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