We're in the market for a backup generator for the house.

We already have propane, so that's the fuel we'll be going with.

Thoughts and advice so that I have a better idea of what to look for when the guy (Generac guy) comes to give us some quotes?

I have a basic understanding of interlock switches vs. transfer switches. I'm leaning toward the transfer switch and probably would like an automatic one, but I see wildly differing prices on the web as I try to get an idea of what is reasonable.

There are a lot of variables in figuring out which model and size to get. I won’t comment on that yet.

The ATS is a great idea. One of the largest selling points for our clients is that with an ATS you don’t have to do anything. So if you’re gone and your wife is home there won’t be any issues.

Also, you might want to verify if you have a large enough propane tank… The minimum size we installed was a 500 gallon. As you know using the tank between 20% and 80% only leaves you with 300 gallons and that’s IF your tank is full when the power goes out…

Tank size is 500 gallons, FWIW.

Are you loking for survival running minimim things like lights and a refrigerator, or the whole house including a central heat pump\water heater\well pump?

IIRC the Generac quote we got was about $18k installed, running on NG.
I forget the sizing, but we held off. May end up doing a manual setup with a portable Dual-Fuel option later.

Oat-Action-Man: installed a 22hp Briggs&Stratton
Whole house unit, 500 gal propane tank, ATS, new 200 Amp panel augmenting a separate 100 amp panel a year ago. The unit runs automatically every week in a monitored test mode. We also had a 9 + hour outage about a month after everything was installed, tested and inspected. All good.
My entire system cost about 15K; 500 gallon propane tank, piping, tested, plus fuel, $2400.
I completely and totally am delighted with what we purchased. The new electrical panel was an added $2200 installed.
Be sure to buy your necessary annual maintenance agreements and monitoring services.
Up until this install, I had owned 2 other Briggs portable systems, and got over 15 years active and very good service from these units. Just got tired outa hauling gas cans!
Our home is rural 2700 square feet, and we can load carry every appliance, and with some load shifting, AC, or heating(also propane). We also pick and choose when it comes to washer/dryer usage.
Regards,
Blackhorse4


T

FWIW…


We live in area with frequent short outages less than an hour, numerous “medium” outages of less than 3 hours (maybe 2-3 over the fall winter yearly) and very occasional long ones 4 hours or more (like a couple years between those). With that, the cost of a whole house Generac setup, just wasn’t practical.

Ended up getting a 7500w dual fuel (propane/gasoline) portable generator and a transfer box wired into the main panel.

The generator connects into 6 circuits giving us all kitchen functionality (gas stove), family room lights/entertainment, furnace, garage outlets (freezer, gas on demand water heater), full master bedroom lights/outlets.

I have a couple large capacity power banks if needed and usually will only fire up the generator if it looks like we will be out of power beyond 4-5 hours. Generator usually gets used just once or twice a year, but have been a few years where it wasn’t needed. Over 15 years there have been two instances where I had to run it for extended period, 2-3 days and another for 6 days.

Even then, I would usually only run it 8-10 hours, give it a few hours rest and then run another 6 hours or so, shutting it down for overnight.


That limited irregular use is why I went with a dual fuel that could use propane. I’ve ruined a few gas generators by letting them sit and ignoring maintenance.

Mom n dad live in western NC and have a whole house automatic transfer switch for the reasons above-if dads not home it’s not a worry for mom to be cutting off stuff and turning on stuff.

Their power goes out at least every other months due to squirrels or car wrecks or trees knocking down lines. It’s been that way forever.

There’s is a generac. And it’ll run the heat, ac, pump, oven and much more. And propane is the way to go. Buy when it’s cheap and it lasts all year. Iirc they have a 1000 lb tank.

We put in a 24KW Generac on new construction in early 2024, on propane with ATS. The switch isn't just for when your poor pitiful spouse is a alone, but if you're asleep, out of town when it's 5 degrees, kids are there, etc. Having it manage turning on once power is out for a preset time (ours is one minute) is glorious.

Please note the total power on propane is slightly different than NG as I recall. Not enough to matter in the end.

We paid $12K for generator and install, but the transfer switch and pad were already in place. Avoided having to re-wire anything.

First time it came on in the heat of summer I felt like a king. We were outside and didn't even know power was out until my SIL said "what's that sound?"

Generators are rated for less power on natural gas than propane.

Automatic transfer switch is fantastic.

You are supposed to check the oil level on the air-cooled Generacs every 24 hours. Oil changes every 200 hours after break in, or every 100 hours if operated below 40 degrees or above 85 degrees. This is OK for a property you live at, not so much for one you don’t. During last April’s ice storm in Michigan, ours ran for 14 days straight. Oil levels were fine when I got up there. We only left them on to run the sump pumps and never figured the power would be out for more than a day or two.

Another cool point if you go dual fuel. I have a Champion 3500 and forgot to start it for a couple years when we didn't have any outages. The starter relay died so no electric start. I learned even without a battery I can pull start on propane and if I'm fast, switch over to gas from there. I got the replacement starter relay but have been using it this way without much issue.

Got my whole house system 2016ish. I got several quotes and the first 4 or 5 guys quoted a limited size system then I got a guy that was a fair sized contractor in our area. He quoted a 22k (biggest at the time) for less then any of the others. Cost wast $7k.
It has been great, longest run was 4 days in HOT weather and never missed a beat.

This reminds me to go change the oil, plugs, & air filter in mine.

We went thru Costco to get our 18kw General - ran about $11k plus we got 10% back in Costco credit. Does the whole house nicely on NG. Power goesout, it comes on after 30 seconds. When power is restored, it shuts off. It turns itself on every Wednesday afternoon for five minutes, then turns off. Quite convenient.

There are people here that sell them, but I will add my 2 cents from buying one and from my research.

Avoid Generac - they have gotten too big and resorted to many Chinese inferior parts (that was per the company that I bought from).

Size it to run about 50% of max capacity at normal loads. This keeps it from running wide open all the time.

Keep maintenance items on hand and learn how to service it yourself. Mine is basically a V-twin riding mower engine. Every 100 hours of run time it needs to be serviced but it is as simple as an oil and filter change. I keep oil and air filters and synthetic oil on hand.

Get ATS then you never have to worry about losing power and swapping over when you are not home.

I'll also add that a big cost add on our quote was having to run wire from the panel to the other side of the house where the NG connection for our pool is.

If I get it requoted, I'll look at having the NG run to the panel side of the house instead.
With how we would have needed to situate it, the exhaust would have blown toward the AC unit & the updraft there would have pushed fumes up to the soffit vents.

Plus, putting it on the panel side of the house gets it away from all the bedrooms & on the garage side where we'd be less disturbed by it running.

quote:

Originally posted by mrvmax:
Avoid Generac - they have gotten too big and resorted to many Chinese inferior parts (that was per the company that I bought from).

This has been true for decades. Kohler is superior to Generac in every respect except price.

I compared the two when we put a 15Kw unit at the farm and it wasn’t even close. Generac is a little better designed than they were back then as far as ease of maintenance goes, but Kohler has always been designed with DIY maintenance in mind and their quality is still much better than Generac IMO.

-Rob

No love for Cummins-Onan whole home generators?

quote:

Originally posted by Johnny 3eagles:
No love for Cummins-Onan whole home generators?

I was going to go with them but ended up with B&S. If I ever get another one it will be Cummins.

I’m in Wisconsin, rather reliable electricity. I am on a well, somewhat weak link. I have a woodstove, dry firewood, and a Honda portable generator.

I really haven’t lost power over 3 hours in 25+ years. I know, could happen tomorrow.

Just saying, for the cost, there are various ways to mitigate risks. If set on the whole house takeover, that’s fine too.

quote:

Originally posted by BurtonRW:

quote:

Originally posted by mrvmax:
Avoid Generac - they have gotten too big and resorted to many Chinese inferior parts (that was per the company that I bought from).

This has been true for decades. Kohler is superior to Generac in every respect except price.

I compared the two when we put a 15Kw unit at the farm and it wasn’t even close. Generac is a little better designed than they were back then as far as ease of maintenance goes, but Kohler has always been designed with DIY maintenance in mind and their quality is still much better than Generac IMO.

-Rob

I've seen a lot of Kohlers with mystery computer issues that couldn't be resolved without multiple trips from the dealer. Cummins/ONAN are by far the best, Kohler in the middle and generac below them.