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Blackout Wall Heaters - Nat Gas Direct-Vent Non-Electric

Gman_3Gman_3 Posts: 27Member
Would welcome feedback on heaters (furnace) that are great backups during an electric blackout that use natural gas and are direct vent. Have come across ones by Empire and Williams. Does anyone have any experience with them or others? Thx. Gman


  • hot_rodhot_rod Posts: 11,259Member
    Rinnai has some small direct vent wall furnace. One model has a 58W power draw. A computer UPS could run it for awhile, or add larger storage deep cycle batteries. Depends on what you want for a run time?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • ch4manch4man Posts: 134Member
    i repaired a gravity boiler a few years back, needed a thermopile.
    millivolt system. gas desgned by the way, sears brand i think from the 60's.
    must have been designed and installed properly. it was fully circulating heated water in short order. they'd have heat even after weeks of a power outage
  • Big Ed_4Big Ed_4 Posts: 1,118Member
    I have installed the Williams units , They work just fine .
    I have enough experience to know , that I dont know it all
  • Solid_Fuel_ManSolid_Fuel_Man Posts: 1,458Member
    I've put in several Empire DV units. Work well enough, definatly not the most efficient. But work very well.
    Master electrician specialising in boiler and burner controls, multiple fuel systems, radiant system controls, building controls, and universal refrigeration tech.
  • JackJack Posts: 1,044Member
    Rinnai has dominated the DV wall furnace market since it introduction in ‘91. HR the unit you reference is the EX22. 8200-21500 input, draws between 33-56 W. Vent kit is included and requires only a 2.5” hole. Simple install and very high reliability. Oh, and I’m no longer affiliated with Rinnai, but have had them in my home, garage and shop since ‘91. I wouldn’t be without them😀
  • DocfletcherDocfletcher Posts: 443Member
    Is there an advantage to these DV wall vent heaters over a back up generator to run your NG boiler?
  • JackJack Posts: 1,044Member
    While that is a short question there is a lot to unpack there Doc. How are you fueling the generator? How big is it and will it supply clean power to the boiler or whatever else you want to run with it. As to an advantage I can only say that it is getting cold. I am not sure what the situation is with the equipment people have in their homes now, given the over pressure. Are the gas valves ok on the units? I do not know where things are going there. The Rinnai DV's are outstanding products and are an excellent option especially in a situation where people need heat now. Once a guy installs a couple of them they can be installed in an hour or two, discounting having to run a gas line. When I lived in Westborough I had a standard two story colonial of 3000 Sq ft. It was a nice house with a conventional Buderus hot water heating system. I installed the EX22 (the preceding model actually) and heated the family room, kitchen area, about 800sq ft, which is actually where we lived 90% of the time. I turned the boiler stat way down and my central system actually became my back-up. If I wanted, I could heat the whole place up in a hurry, but I don't have friends so no one ever came over and I hardly ever had to do so.
  • Solid_Fuel_ManSolid_Fuel_Man Posts: 1,458Member
    No friends? Sad!

    I will speak to the reliability and beautifully robust engineering of the Rinnai direct vent wall furnaces.

    But the OP wants something non-electric I assume. That leaves Williams and Empire.
    Master electrician specialising in boiler and burner controls, multiple fuel systems, radiant system controls, building controls, and universal refrigeration tech.
  • JackJack Posts: 1,044Member
    I have had this conversation for the last 28 years. My response to this is "cheap heat or cheap heater." Over the years whenever the discussion of just about anything heating comes up I simply say, "Well, I can heat the place by building a little camp fire here in the living room. Is that ok?" They of course respond with a negative. At that point, it is a matter of "features, benefits & value" and at that point you get to educate the customer. A non-electric is 60% efficient, single stage, hot to the touch, a 12" hole in the wall for the vent. They make heat but do not heat well. Certainly it is the customers choice, but not in the same category.
  • DocfletcherDocfletcher Posts: 443Member
    Jack, I'm speaking of the Natural Gas generator like a Generac for your NG boiler.. The ones that are fixed in place outside the home and come on when the power fails. I personally do not have one, but during power failures I use a small 4000 watt gasoline generator and tie it into the NG boiler for heat. Inexpensive heating option for me that has served me well over the years. I'm considering an automatic Generac because it will come on even when I'm not here keeping the home warm. The OP spoke of heat in power failure situations, the folks who are dealing with the over pressure issue certainly would need to find another way for heat, such as the Empire.
  • Solid_Fuel_ManSolid_Fuel_Man Posts: 1,458Member
    I'd not rely on NG for backup. Think about what we are seeing with the Columbia incident. In the rural parts where I live everyone has an old wood stove and 1/2 cord of wood in the basement.

    When all else fails, we go back to wood.
    Master electrician specialising in boiler and burner controls, multiple fuel systems, radiant system controls, building controls, and universal refrigeration tech.
  • Gman_3Gman_3 Posts: 27Member
    Thank you all for you feedback. As much as I'd like to use a UPS for battery backup, 60 watts is a 5 amp draw on a 12v battery with the old math and that not with any conversion loss either!
    The only wall units I could find were the Williams and Empire and at least of few of us Wall users have some experience with them but am still surprised that the units aren't more popular. During a blackout, am fine with efficiency going out the window :-) but at least they are direct vent! (I'll start another thread later re pellet stoves that don't use electricity).

    Generators are nice to have but require maintenance. Some of the Generacs can go 250 to 500 hrs before oil changes at least. So many people ran out of oil during Hurricane Sandy. But a wall heater will just burn and burn (in theory).

    Any more feedback on non-electric NG wall heaters is appreciated? Thanks in advance.
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