hooking up a portable generator to your hvac system

billy backstay

Backstay, never bought a suit, never went to Vegas
Do it right. Install a power transfer switch.

Dunno what that costs, since the previous owner had already had one installed. We added a 3 ton split system AC with heat when we moved in 3 years ago, and just recently had the electrician add that to the genset circuits. Now the only thing our 7.5 KW genset won't run is the clothes dryer, and electric oven. And we have to turn off the electric water heater in the garage loft apartment, if we want to run the AC. Or vice-versa, if we don't need the AC, and want hot water in the apartment. I do need get some fresh gas, since the jug sitting next to the generator in the basement is 2 years old, so will mix it with fresh regular gas in the pickup truck and replace with fresh gas, and Startron additive. I start it up with a little bit of gas once a year to make sure it's still good, then let the gas run out, so nothing left in the carb to muck it up.
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dyslexic dog

Super Anarchist
3,892
343
Michigan
AAAHHHHHHHH, I always read these posts and the responses and I realize how lucky I am to still be alive. It's like listening to Bullwinkle talk about upsidayzinum. If you don't understand it, don't do it. Get someone who does or you can hurt someone.
 

peragrin

Super Anarchist
1,827
81
Dunno what that costs, since the previous owner had already had one installed. We added a 3 ton split system AC with heat when we moved in 3 years ago, and just recently had the electrician add that to the genset circuits. Now the only thing our 7.5 KW genset won't run is the clothes dryer, and electric oven. And we have to turn off the electric water heater in the garage loft apartment, if we want to run the AC. Or vice-versa, if we don't need the AC, and want hot water in the apartment. I do need get some fresh gas, since the jug sitting next to the generator in the basement is 2 years old, so will mix it with fresh regular gas in the pickup truck and replace with fresh gas, and Startron additive. I start it up with a little bit of gas once a year to make sure it's still good, then let the gas run out, so nothing left in the carb to muck it up.
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I bought my 7.5kw generator as dual fuel so it runs on propane. I fire it up on propane once a year and the 5 gallon gas cans get used for everything else. Between my grill and camper i have 3 20 pound propane tanks and 1-2 5 gallon gas can giving me 2-3 days of careful usage.

Yransfer switch costs very but i spent 2500 to ipgrade my 100 amp service to 200 amps and had them include a generator transfer plate in the panel. Ie i turn off the main breaker lift a lever and turn on another breaker and my entire panel is switched over.
 

billy backstay

Backstay, never bought a suit, never went to Vegas
I bought my 7.5kw generator as dual fuel so it runs on propane. I fire it up on propane once a year and the 5 gallon gas cans get used for everything else. Between my grill and camper i have 3 20 pound propane tanks and 1-2 5 gallon gas can giving me 2-3 days of careful usage.

Yransfer switch costs very but i spent 2500 to ipgrade my 100 amp service to 200 amps and had them include a generator transfer plate in the panel. Ie i turn off the main breaker lift a lever and turn on another breaker and my entire panel is switched over.

I have yet to try and run our dual fuel model on propane because it uses so much, and I would have to have a code-compliant gas pipe installed from the 100 lb tank to where I roll the Genset out of the basement to. I suppose I could try it with smaller tanks like the gas grill uses but haven't seen the need to yet. Just running on petrol pump gas, we get a full day on the 4-gallon tank and turn it off at night, when going to bed. Only one lever turns off the street power and switches it over to Genset power.
 

Pertinacious Tom

Importunate Member
62,073
1,884
Punta Gorda FL
Was that guy a line man? When running line outage crews , if we heard a generator running, we'd pull the guys down and walk the neighborhood, and make sure all Generators were off, better safe than sorry, also if generators weren't hooked up right, I've seen hot neutral's

I was driving down a rural road and saw an FPL crew with a drone, inspecting the lines, pretty cool
We unplugged the meter to hook up the generator after Charlie.

The power co guys I talked to said they liked that approach a lot better than just throwing the main breaker because it's more visible and less likely to be undone inadvertently.

I never knew that the meter is just a big plug until I watched my neighbor pull it out (and toss it on the ground.)

A week or so after the storm, the generator was running and my wife was sitting in the shade because it wouldn't run the AC. A power co guy appeared, startling hell out of her, and said, "Ya'll can plug your meter back in now," and turned to leave. She yelled after him to confirm his message.

We got power that quickly because they were fixing the line to the water plant. My line connected to that one was one of few that didn't fall in the storm. My neighbor was on his generator for a couple of months before they got around to restoring individual lines in rural areas.
 

Marcjsmith

Super Anarchist
3,883
1,047
Washington DC
May sure you turn off Main Breaker, coming into the house, As a back feed to a transformer could electrocute, a line man on the poles trying to restore service
I have a 5500 watt generator it will run everything in the house, except the ac. The start up load is too much. But I have a gas furnace and it will run fine. I have a 30 rv plug for when my folks are in town. So I reverse feed the house with the generator. Yes it has a male male plug, yes I have separate house disconnect so I can take my home off the grid.

Easy to do, but if you are not careful you can hurt someone.
 

Pertinacious Tom

Importunate Member
62,073
1,884
Punta Gorda FL
I have a 5500 watt generator it will run everything in the house, except the ac. The start up load is too much. But I have a gas furnace and it will run fine. I have a 30 rv plug for when my folks are in town. So I reverse feed the house with the generator. Yes it has a male male plug, yes I have separate house disconnect so I can take my home off the grid.

Easy to do, but if you are not careful you can hurt someone.

I ran a line from the 30 amp 220 plug on the generator to my house service disconnect panel. The FPL meter is safely on the ground so I don't energize the wires laying in the yard. I didn't do it in a way that they recommend on This Old House. But it's working.

Then I thought it would be nice to have lights at my other house. I made a male/male extension cord and plugged it into the 15 amp 110 plug on the generator and into a socket in the little house. Success! Almost everything I want has power over there. The exception is the lights I use most, which are on a breaker on the dead side of the panel. All the other slots on that side are 220 feeds.

So if I run a jumper from the hot side to the dead side of the breaker panel and leave all the 220 switches off, would I get power to the lights I want? Seems like it should work but I know just enough to be dangerous sometimes.
 

Junkyard Dog

Super Anarchist
2,880
14
N/A
I've got a 10K/12K start up, dual fuel generator hooked up to a Reliance Control 50 Amp, 10 circuit transfer switch. I can selectively run the AC or the heat plus 7 other circuits. This includes the fridge, microwave, and some lights and fans around the house. It's not a full house solution, but enough to get us by.

Note, load balancing is important. Hence the two Watt meters. Need to keep them somewhat even.

I can't run the stove/oven, or the dryer for example. We have a gas water heater so as long as the MUD provides water pressure we are OK on that front. We got through Ike alright, flooded in Harvey, survived the big February freeze (barely) and set up this rig last year. I've got a supply of propane to run the generator, as well as a rotating stock of gasoline. As long as Abbott and his donors run the Texas grid, I'm not taking any more chances.

510C_1_2000x.progressive.jpg
 
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Junkyard Dog

Super Anarchist
2,880
14
N/A
We unplugged the meter to hook up the generator after Charlie.

The power co guys I talked to said they liked that approach a lot better than just throwing the main breaker because it's more visible and less likely to be undone inadvertently.

I never knew that the meter is just a big plug until I watched my neighbor pull it out (and toss it on the ground.)

A week or so after the storm, the generator was running and my wife was sitting in the shade because it wouldn't run the AC. A power co guy appeared, startling hell out of her, and said, "Ya'll can plug your meter back in now," and turned to leave. She yelled after him to confirm his message.

We got power that quickly because they were fixing the line to the water plant. My line connected to that one was one of few that didn't fall in the storm. My neighbor was on his generator for a couple of months before they got around to restoring individual lines in rural areas.
Well, that's amazing. Around here if you break the seal on the meter you're in big trouble. You have to pull a permit to reinstall, have an electrician sign off on the job, and the utility reinstall the meter and put on their seal.

Welcome to Texas.
 

Pertinacious Tom

Importunate Member
62,073
1,884
Punta Gorda FL
Well, that's amazing. Around here if you break the seal on the meter you're in big trouble. You have to pull a permit to reinstall, have an electrician sign off on the job, and the utility reinstall the meter and put on their seal.

Welcome to Texas.
After Charley, we did as the man suggested and plugged our meter back in. We did it right then, with no inspection. I guess at some point they came around and put a little lock on it again.

We put another house on the property since then so now there are two meters. Both safely on the ground at the moment.

In other news, my generator will run my water heater so I can have a hot shower after my wife wakes up.
 

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