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reliabilityman

Emergency Furnace Wiring Question?

reliabilityman
17 years ago

Hi, I am stuck in this great ice storm that is sweeping the nation. I have reports from my city leaders that it may be 2 weeks before we recieve power again. I have been living off a 5000 watt generator for 4 days now in one room of the house, but the rest of the house has dropped to 40F. Outside it is single digets today. I had a thought today on how to get my gas furnace back on, but I am not an electrician, but have wired up some garage fixtures etc. Enough to sort of know what I am doing. But I want to shoot this out to all who read and hopefully provide me with some feedback. Currently my furnace is fed from the outside pole through the breaker box, through a 15AMP breaker to the furnace. I thought I could shut the power off at the breaker, remove the wire on the side to the furnace, install a 110 V plug to the wire and plug it into my 5000 watt generator to get the furnace on. The only thing the furnace relies on is the electronic ignition, 1/3 HP 1.3 AMP blower motor, and low voltage for the thermostat. All the controls tend to be on the inside of the furnace. The only thing I was planning to do is to provide the 110 from the generator and not the pole like normal. My wife thinks I will burn the house down, but I am getting desperate. Any thoughts or does this sound like a real bad idea? I really don't think the gas furnace draws much at all since it is on a 15AMP breaker.

Thanks

Comments (11)

  • bob_brown
    17 years ago

    Hello,
    You are going in the right direction. Disconnect the power to the furnace. This is a 110vac connection. The draw is probably about 8 amps. Connect the furnace directly to the generator thru an ex cord. You may not have enough power for many lights. If you have CF flourscent bulbs use them instead, they do not need as much power. Ask more questions.

  • reliabilityman
    Original Author
    17 years ago

    Thanks I have checked with an electrician friend and he says this is the way to go. I am going to use SO cable with a plug on one end and wired to the furnace on the other. I will completely disconnect the furnace from the house wiring so there is no chance of feedback to the electric pole.
    Normally I would not mess with this but these are desperate times!!!

    Thanks

  • blacknumber1
    17 years ago

    Make sure you get the polarity correct and connect the ground as well or the furnace will not work correctly. Just disconnect the furnace wiring and connect an A/C plug to it. You could also cut off the pigtail of a heavy-duty extension cord and wire-nut it to the furnace connections. Make sure your connections are snug and your thermostat is all the way down or turned off completely, some furnaces will not work if the thermostat is calling for heat when you power them up. Connect to your generator cords, fire it up and turn on/up your thermostat.

  • yzfoot
    17 years ago

    Just a side note on what was said earlier. 5000 W is quite a bit. I'm 3 days into an outage too. My generator is 4000W and I am able to run most of the house on it just like normal with a few limitations. I havn't tried the electric stove or dryer but I do run the furnace, well all the lites I want, tv, computer etc. and its not a small house. I'm wired 220 into the box. Don't think your 5000W is small. Next chance ya get pay an electrician and plan to be comfortable next go around.

  • reliabilityman
    Original Author
    17 years ago

    Good news, Last night I made my custom 100'SO chord extension cord and plugged it into the generator on one end, and wire nutted the wires to the furnace on the other end. The furnace fired up and ran just like normal. It ran for 4 hours straight to bring the house up from 40F to 70F. It felt so nice to have heat again after 4 days. I almost stripped down to my b-day suit and enjoyed the warmth!!!-HA
    It was so easy to get this going, I am kicking myself for not doing this 4 days earlier. The energy used to heat 1 room from a small electric space heater was more than it was to run a 1/3 HP fan in the gas furnace to heat the whole house!!-Duh. Well next time (I hope that there is not a next time) but if there is I am well educated and prepaired.

    yzfoot,
    You must have some sort of permanent generator with a transfer switch installed so you can run it to your panel I am guessing? I am running off of your run of the mill portable generator. I actually bought it 2 years ago to help build a barn in a remote area that had no electric power access for miles around. Funny thing was I debated on renting a generator or buying this one from Sam's Club. I figured after I plunked down $500, and after the barn project was over, I would be cussing this thing for years as I moved it out of my way in the garage. Well for 2 years I had done that, but the last 4 days I would have paid 3 times that to have one, and it was good as gold. Especially now that I can run the furnace. Funny how life works sometimes.

  • bob_brown
    17 years ago

    Hello,
    Probably the best way to have a transfer switch with a limited size generator is to have the specific circuits you wish to power, isolated from the main circuit panel, with the transfer switch or a plug to the seperate circuits. Some of your lights, and the heater. Maybe the refrigerator also. I would imagine that in a cold climate, you could easily have a cold storage closet for foods that is cooled by the ambient outdoor air.

  • reliabilityman
    Original Author
    17 years ago

    bob brown,
    You are correct, with this storm, refridgeration was not a problem. In fact I unloaded the fridge and freezer 2 times, once when we lost power for 4 hours, then I put it all back, then when we lost it for the last and greatest length of time-4 days. Ambient air has taken care of these needs for now. If it was summer, then I would have a real different problem. But not a bad idea.

  • blacknumber1
    17 years ago

    I've actually seen little 1000W generators for about $100. I'm sure theyre noisy, probably wont last and only really put out about 800 watts, but that can run a furnace, frigde or some lights. Cheap insurance if you ask me!

  • jimprayn
    17 years ago

    I just purchased a generator and a transfer switch to connect to my furnace.All the wiring diagrams that I have seen show the transfer switch being wired into the breaker box. I want to wire mine directly into the furnace using the on/off switch on the furnace. This will be easier to run the extension cord the furnace than the breaker box.
    Can I do this, and how?

    Thanks,
    Jim

  • tazk9
    16 years ago

    Do you guys have any Pics of this type of a set up? We are in the middle of a monster winter storm and Im expecting the power to go out and would love to see how to wire up the gas furnace to my 5000 watt generator. I read the description, but im more of a visual learner and would like to see exactly which wires to connect to a plug.

    Thanks Steve

  • Mylestone_comcast_net
    13 years ago

    Does anybody have a wiring diagram and parts list to correctly wire my generator up to my peerless 1/7 hp oil burning furnace blower motor and circulate pumps? I really need to save some cash after the generator purchase and I can follow a wiring diagram.I also have to cut the city current so I don't fry the generator!
    HELP
    Myles