Backup generator - unusual implementation

[dvg]

Wondering if I could provision my house to use a backup generator by putting a 240V outlet in the garage. Would be nice to keep power going to the fridge, furnace, water heater during a power outage. Here is what I have in mind...

In the event of a power outage, turn off the main 100A breakers, flip off any breakers that you dont want to provide power for, and plug a portable 240v generator in the garage into the garage outlet. Open garage door for ventilation.

A bonus is that youd have a 240V outlet for an electric vehicle in the future.

This would work in my mind but Im not an electrician. Id certainly consult an electrician before pursuing this.

Not sure if the breaker running to the garages 240v connection would work in reverse or if Id need some kind of special double throw breaker.

[dvg]

After a bit more research it seems that the accepted method would be to put those critical utilities on a load transfer switch like this in order to eliminate the possibility of feeding into the grid.

https://www.homedepot.ca/en/home/p.6...000789434.html

[dvg]

Now Im thinking I may as well just get the builder to put the water heater and furnace on the same circuit if possible, and just add one of these in-line:

https://www.homedepot.ca/en/home/p.t...001061743.html

[BartBandy]

Furnace has to be on it's own circuit.

[GregS]

Water heater needs its own circuit.
Air-handler needs its own circuit.

Yes a transfer switch is what you need for those circuits.

Consult a company that puts in generators. Furnaces can be tricky items to run reliably on inexpensive portable generators because they put out crap quality power.

[dvg]

Possible to put the well pump and the water heater on the same circuit, anyway? (forgot I even had to worry about the well pump, would be first house off of municipal water)

[xdarrylx]

Do you anticipate your power going out that much that you need a generator?

[BartBandy]

I've been known to run my tankless gas-powered water heater with my big computer UPS during power outages before, so we could get a shower or whatever. Doubt it would run the furnace fan.

[suezuki650]

Originally Posted by GregS

Water heater needs its own circuit.
Air-handler needs its own circuit.

If the water heater is gas, but has a power vent, would it still need it's own circuit? After the last power outage, I purchased a generator. I won't be tying it into the house systems, but will be plugging in things like my freezer, fridge and I was thinking my gas water heater. I didn't think the power vent would take much electricity.

[BartBandy]

I know they didn't used to, and my water heater is on a shared circuit from the builder, but that may have changed.