Just getting ready for another snow blast even here in Oklahoma. Didn't lose power this last round, but you never know. Last year my neighbor helped me hook up my heater, natural gas fed, and I can't remember how we did it. We found the three hot lines going into the HVAC itself. Black, white and green. I had a heavy guage extension cord that had a screw in plug, he took that off and screwed in the power lines to the extension cord. What I don't get is do they go to a specific place? The green one gets screwed into the bottom, it's the one with the bigger prong, but are they specific poles that the white and black lines get connected to? I mean, it's AC, so how can I tell which ones go where? It's a 3 prong heavy duty extension cord, under 20 amps. I hook that up to the extension cord and then plug it in to the generator. Worked like a charm last year, I just don't remember exactly how he hooked it up. Thanks for any information on this. I think I phissed off the neighbor Saturday and afraid to ask him again.
Hooking up my generator to HVAC
- Thread starter Schmoe
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This is a "if you have to ask" question...
Green is ground but gound is also bonded to neutral. Grounding generators is.... tricky!
If your appliance is single insulated, the chassis should be neutral. Reverse the wires and it's live! Touch it and, say, a sink at the same time and you fry.
Fortunately your extention cord appears to follow standard wiring colors like you'd find in the hard wired section of your boiler. If you took the cover off you should (should) find black and white in there as well.
Whenever I use a generator I include a computer power strip in the chain. If something starts going down like electrocution it's easier to kick the switch than yank the cord. (Muscles contract and grab harder when they get juiced.)
Obligatory
turn off your main breaker and the boiler breaker warning. Leave either on and you back feed to the rest of your house/ the neighborhood/ the guy fixing the wires.
Green is ground but gound is also bonded to neutral. Grounding generators is.... tricky!
If your appliance is single insulated, the chassis should be neutral. Reverse the wires and it's live! Touch it and, say, a sink at the same time and you fry.
Fortunately your extention cord appears to follow standard wiring colors like you'd find in the hard wired section of your boiler. If you took the cover off you should (should) find black and white in there as well.
Whenever I use a generator I include a computer power strip in the chain. If something starts going down like electrocution it's easier to kick the switch than yank the cord. (Muscles contract and grab harder when they get juiced.)
Obligatory
Have someone help you. I wont give any advice here other than - keep that genset well away from the house and NOT in the garage. Some poor guy killed his whole family up here (MA) by running the genset in the garage.
Originally Posted By: Schmoe
What I don't get is do they go to a specific place? The green one gets screwed into the bottom, it's the one with the bigger prong, but are they specific poles that the white and black lines get connected to? I mean, it's AC, so how can I tell which ones go where?
If you are connecting the wires to a standard 120V plug, there should be a brass screw and a silver screw. The white goes to silver and the black goes to brass.
What I don't get is do they go to a specific place? The green one gets screwed into the bottom, it's the one with the bigger prong, but are they specific poles that the white and black lines get connected to? I mean, it's AC, so how can I tell which ones go where?
If you are connecting the wires to a standard 120V plug, there should be a brass screw and a silver screw. The white goes to silver and the black goes to brass.
Don't jury rig it. Install a transfer switch and hook the generator up to the circuit correctly.
It's clear that you don't know much about electrical wiring so you'll be much better served by having a qualified electrician get things installed in a manner that won't backfeed the system or cause other issues that a layperson pretending to be an electrician can cause.
It's clear that you don't know much about electrical wiring so you'll be much better served by having a qualified electrician get things installed in a manner that won't backfeed the system or cause other issues that a layperson pretending to be an electrician can cause.
JHZR2
Staff member
I was about to ask a similar question but with my proposed plan... Ill do it in a separate thread. You can reference it if need be, should indicate how to do it with comment from the collective.
The black is the "hot" wire, it is also the BIGGEST flat prong on the cord & receptacle, the neutral is the white wire (also connected to ground in an electrical panel, NOT on your generator), the green is ground-the round prong on your plug and generator. If your heater has solid state electronic controls be SURE to use a spike protector (strip or single type) and a GFCI/ground fault is also an excellent idea (I have one on a short cord I use myself). Be SURE to position your generator DOWNWIND from your house!
Roger on the gen. placement. Used it last year for about 4 days and all worked out well. It's placed well outside from the garage. I think Brianl703 hooked me up. It's a standard 120V recepticle. Should have said that but I didn't. I do turn off the main breaker coming from the power meter. Didn't think about plugging into a spike protector prior to heater hook up, thanks for that. May explain why my blower motor circuit board fried on me about a month ago. Could have been damaged since last year and I just been lucky this past summer. There is actually a 240 plug under the breaker box. Guess prior owners had a arc weld or something. I told myself I'd get a plug to go from the 240/30 amp gen. outlet to the 240 plug in the garage instead of having to rig up an extension cord this past summer, but I didn't. I actually called an electrical shop and they said I can't do that. As long as I turn off certain breakers and shut down the main breaker, it will work, like back feeding, just have to keep the main off until power gets restored and disconnect.
Originally Posted By: bullwinkle
The black is the "hot" wire, it is also the BIGGEST flat prong on the cord & receptacle, the neutral is the white wire (also connected to ground in an electrical panel, NOT on your generator), the green is ground-the round prong on your plug and generator. If your heater has solid state electronic controls be SURE to use a spike protector (strip or single type) and a GFCI/ground fault is also an excellent idea (I have one on a short cord I use myself). Be SURE to position your generator DOWNWIND from your house!
If you meter it out you will find the largest prong on a regular 15 amp plug or receptacle is the neutral.
The black is the "hot" wire, it is also the BIGGEST flat prong on the cord & receptacle, the neutral is the white wire (also connected to ground in an electrical panel, NOT on your generator), the green is ground-the round prong on your plug and generator. If your heater has solid state electronic controls be SURE to use a spike protector (strip or single type) and a GFCI/ground fault is also an excellent idea (I have one on a short cord I use myself). Be SURE to position your generator DOWNWIND from your house!
If you meter it out you will find the largest prong on a regular 15 amp plug or receptacle is the neutral.
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Just wanted to confirm Andyd is correct. The small vetical prong is for hot (Black) and the large is neutral (white) . You'll still have 120 volts if you reverse it, though.
I could give some advice but am hesitent to because I can easily see many things being done wrong.
Just make absolutely sure you are cannot back feed power to the utility by having your main breaker open if you tie anything into your existing wiring.
I could give some advice but am hesitent to because I can easily see many things being done wrong.
Just make absolutely sure you are cannot back feed power to the utility by having your main breaker open if you tie anything into your existing wiring.
JHZR2
Staff member
OK so Ill ask here then since we're getting on the same topic.
My parents have an oil/coal stoker in their home. It is fed on a 15A circuit. That circuit has an electrical outlet on it.
If and only if the service breaker was open and tagged out somehow, would it be acceptable to run a small generator capable of the 15A (or furnace load), and then backfeed through that plug by making a dual male jumper? Then the generator could be put far away and downwind, a 10ga extension cord could connect and the jumper would allow backfeed of power into that circuit to run the furnace.
Of course then the generator would be isolated prior to re-closing the service breaker in the panel.
This would allow the house to be heated in a pinch, and since one would need to know what they were doing, only certain users could connect the gen to the furnace... after opening the breaker.
Im interested in this too, as my new ultra-high efficiency furnace has a blower and electrical controls... which wouldnt run in case of a power outage. Assuming gas still flows, would be nice to make heat. As I dont have a suitable size generator, it would be nice to simply be able to power my system under specific restricted conditions that Im aware of and are controlling...
Thanks!
My parents have an oil/coal stoker in their home. It is fed on a 15A circuit. That circuit has an electrical outlet on it.
If and only if the service breaker was open and tagged out somehow, would it be acceptable to run a small generator capable of the 15A (or furnace load), and then backfeed through that plug by making a dual male jumper? Then the generator could be put far away and downwind, a 10ga extension cord could connect and the jumper would allow backfeed of power into that circuit to run the furnace.
Of course then the generator would be isolated prior to re-closing the service breaker in the panel.
This would allow the house to be heated in a pinch, and since one would need to know what they were doing, only certain users could connect the gen to the furnace... after opening the breaker.
Im interested in this too, as my new ultra-high efficiency furnace has a blower and electrical controls... which wouldnt run in case of a power outage. Assuming gas still flows, would be nice to make heat. As I dont have a suitable size generator, it would be nice to simply be able to power my system under specific restricted conditions that Im aware of and are controlling...
Thanks!
Gentlemen, I appreciate your reservations but I'm not an idiot. I've done this before and just wanted to be sure my thinking was sound before, I pray that I don't have to, generator power is warranted. Last year, I ran the heater and a whole bunch of stuff off of this generator through good, heavy extension cords. Worked well actually and luckily the local gas station still had power. I know to shut off the main breaker, and it wasn't until I went outside that I realized that power had been restored. I made a promise to myself that since these winter storms seem to get worse every year lately, I'm going to have it wired correctly by a professional, however, I'm just making sure I'm thinking right on the heater hook up. I know the green is ground and black is hot and white is neutral, whereas black is ground on a DC circuit. I just wasn't sure if there is an exact and only way to hook up the black/white lines to an extension cord. I would have tested it out on something a lot smaller, like a cheap lamp, to see if it actually worked before embarking on the central heater, which would be the live blood of the house during a blizzard. Anybody got anything on grounding the generator itself??
Originally Posted By: JHZR2
OK so Ill ask here then since we're getting on the same topic.
My parents have an oil/coal stoker in their home. It is fed on a 15A circuit. That circuit has an electrical outlet on it.
If and only if the service breaker was open and tagged out somehow, would it be acceptable to run a small generator capable of the 15A (or furnace load), and then backfeed through that plug by making a dual male jumper? Then the generator could be put far away and downwind, a 10ga extension cord could connect and the jumper would allow backfeed of power into that circuit to run the furnace.
Of course then the generator would be isolated prior to re-closing the service breaker in the panel.
This would allow the house to be heated in a pinch, and since one would need to know what they were doing, only certain users could connect the gen to the furnace... after opening the breaker.
Im interested in this too, as my new ultra-high efficiency furnace has a blower and electrical controls... which wouldnt run in case of a power outage. Assuming gas still flows, would be nice to make heat. As I dont have a suitable size generator, it would be nice to simply be able to power my system under specific restricted conditions that Im aware of and are controlling...
Thanks!
Dual male jumpers work but are bad bad bad. They're called "suicide plugs".
It may be worthwhile to see if you can get a standard but locking 110 v receptacle and convert your furnace to a short pigtail with male plug. Then if the power goes out you can unplug it from the wall outlet and straight into an extention cord.
IIRC it's code that permanently installed stuff like furnaces have to be permanently wired... but the locking plug may meet that.
Even if you have to use a "twist loc" plug as long as it's wired correctly you can put another female twist loc on your "generator extention cord".
This debate adds debate:
http://www.contractortalk.com/f6/furnace-plugged-wall-outlet-18486/
OK so Ill ask here then since we're getting on the same topic.
My parents have an oil/coal stoker in their home. It is fed on a 15A circuit. That circuit has an electrical outlet on it.
If and only if the service breaker was open and tagged out somehow, would it be acceptable to run a small generator capable of the 15A (or furnace load), and then backfeed through that plug by making a dual male jumper? Then the generator could be put far away and downwind, a 10ga extension cord could connect and the jumper would allow backfeed of power into that circuit to run the furnace.
Of course then the generator would be isolated prior to re-closing the service breaker in the panel.
This would allow the house to be heated in a pinch, and since one would need to know what they were doing, only certain users could connect the gen to the furnace... after opening the breaker.
Im interested in this too, as my new ultra-high efficiency furnace has a blower and electrical controls... which wouldnt run in case of a power outage. Assuming gas still flows, would be nice to make heat. As I dont have a suitable size generator, it would be nice to simply be able to power my system under specific restricted conditions that Im aware of and are controlling...
Thanks!
Dual male jumpers work but are bad bad bad. They're called "suicide plugs".
It may be worthwhile to see if you can get a standard but locking 110 v receptacle and convert your furnace to a short pigtail with male plug. Then if the power goes out you can unplug it from the wall outlet and straight into an extention cord.
IIRC it's code that permanently installed stuff like furnaces have to be permanently wired... but the locking plug may meet that.
Even if you have to use a "twist loc" plug as long as it's wired correctly you can put another female twist loc on your "generator extention cord".
This debate adds debate:
http://www.contractortalk.com/f6/furnace-plugged-wall-outlet-18486/
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