20KW Standby Generator Recommendations

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I was recently without power for three days following Hurricane Michael. In Jan. 2017, I was without power for seven days as a result of a tornado. I have decided that I need a standby whole house generator. It looks like I will need a 20KW unit. I am looking at three different brands, Briggs and Stratton, Cummins and Kohler. All three are powered by air cooled big block V-Twin engines. Anyone out there have any of the brands I listed and how well do you like them?
 
I've been comparing and shopping here in North Florida, I'm planning on installing a 22KW Generac. I would prefer the Kohler V twin engine over the Briggs Vanguard but for local sales and support the best dealer is a Generac dealer. I wish there was an affordable diesel or 1800 rpm liquid cooled option, but there's not.

So personally I'm buying a Generac. Installation is basically equal to the price of the Generator. So be ready for that. Since I don't have natural gas where I live I'm stuck with propane which is an additional expense. I'm burying a 500 gal tank to run my Generac.
 
Yea, the liquid cooled models are usually 4 cylinder Ford or GM offerings and they are about twice the price. I've had good luck with B&S engines in the past and both the B&S and Cummins come with the 993cc Vanguard engine. The Kohler looks to be a solid unit as well. I'll be using propane as fuel. Propane has the advantage over natural gas.
 
Brother in Law has a Generac 14kw with the Nexus controller board. Known problem with the units affected shutting down upon startup with a "low voltage" error message (all sizes).

Apparently the brushings are problem, and have to be replaced, some with less than 100 hours run time. Not a problem if you identify before the warranty is up, but others like my BIL are screwed because it appeared after warranty period, even tho' it is a known problem.

Make sure you have a revised unit. From what I've read, small dealers may not be aware of the issue, but larger ones are familiar.

His has the Kohler v-twin 992 engine. Nexus controller board is the problem, not the engine.
 
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I've had a 16kw Generac with the 990 twin run on LP for 12 years. It has never malfunctioned or broken down, but it is now close to totally rusted out. Not the cabinet, but the steel frame and base. I'm considering an Onan or Kohler 20kw replacement mostly because of their longer warranties. My Generac had a two year warranty and started rusting badly after three years. The company knew it had a problem with its cheap steel imported from China, but it did nothing to help consumers. That's what irritated me the most.

But be prepared for this. After you install one, you may not have a major outage for several years. That's what happened to me.
 
You never know when you will have an extended outage. According to Norwall Power Systems, Briggs and Stratton has the best warranty among Generac, Kohler and B&S. I haven't looked at the fine details of the Cummins unit.
 
I've had a Kohler 20RES-A for three years. It's been solid so far, although I haven't had to really put it to use yet. I live in the New Orleans area and was without power for around a week for both Gustav and Isaac. I had a portable Honda powered gen that serves me well through both of those outages. Decided to upgrade and fortunately haven't had the need to use it. I run it on natural gas, and it will run my house with 7 tons of A/C no problem. It's fairly easy to work on. I left the lid up after servicing it before Nate last year, and it got rained on and ruined the control board. I found a replacement locally and installed and calibrated it myself no problem. But, I think the others are quality as well. I know people who have Kohler, Generac, and BS and they are all pleased.
 
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That particular Kohler unit is one of those I am looking at. There may not be a great need for one now but, you never know. I have sleep apnea and need a CPAP machine to sleep. I didn't get a whole lot of sleep when our power was out. As my wife and I age, one or both of us may need oxygen or nebulized medication. Being without power under those circumstances is unacceptable.
 
Originally Posted by FlyNavyP3
. I wish there was an affordable diesel or 1800 rpm liquid cooled option, but there's not.


Seek out a motorhome salvage yard. Kubota diesel units are common in the big ones.

I don't believe in going so big as to have "Whole House"...
A small unit burns way less fuel -
and we can all sleep in the one room with a window unit.

Multiply gallons per hour under full load ... by 24 hours... by several days - that's a lot of fuel!!
 
Originally Posted by MParr
That particular Kohler unit is one of those I am looking at. There may not be a great need for one now but, you never know. I have sleep apnea and need a CPAP machine to sleep. I didn't get a whole lot of sleep when our power was out. As my wife and I age, one or both of us may need oxygen or nebulized medication. Being without power under those circumstances is unacceptable.


Get a prius and inverter. The engine will start itself as needed to keep the power up. Those machines don't take a whole lot of power.

I wonder where we are in home standby generators as far as inverter/ battery tech is involved. Dumb to have 2 cylinders and 3600 RPM for 40 watts.

In seriousness I have co-workers with whole-house standby generators. They like that they come on automatically when they're out of the house, so food doesn't spoil etc. They then assume manual control and run a smaller generator to save fuel/ noise when they get home and shed loads.
 
Some units have load shedding capabilities. I don't need the worry of hooking up portable generators. If there is a widespread power outage just where are you going to get gasoline or diesel fuel? Propane doesn't go bad.
 
Originally Posted by Linctex
Originally Posted by FlyNavyP3
. I wish there was an affordable diesel or 1800 rpm liquid cooled option, but there's not.


Seek out a motorhome salvage yard. Kubota diesel units are common in the big ones.

I don't believe in going so big as to have "Whole House"...
A small unit burns way less fuel -
and we can all sleep in the one room with a window unit.

Multiply gallons per hour under full load ... by 24 hours... by several days - that's a lot of fuel!!


If it's was just me I'd buy a 2-71 Detroit Diesel ex-rail car generator and a used 275 gallon fuel oil tank. 20kw low RPM low fuel flow. But since I'm in the military and the other half would be unable to get it running transfer loads etc I want something automatic. Likewise she's unable to lug out a generator, install a window AC unit, plus the inconvenience of hauling or storing gasoline and running cords everywhere. I fully recognize that a whole house standby unit is expensive and not at all efficient but it's what suits my needs the best.
 
Same here. Diesel and gasoline degrades. We had area wide power outages and there was no power to fuel stations. Load shedding capabilities will reduce the fuel consumption. An air cooled unit will give good service as long as it's maintained properly.
 
Have you thought fuel? How much will you need? One week, two weeks, six weeks? Where are you putting the tank? Why not a small and large portable?
 
Originally Posted by Blueskies123
Have you thought fuel? How much will you need? One week, two weeks, six weeks? Where are you putting the tank? Why not a small and large portable?


I'm using a 500 gal propane tank, sized based on a week of power if we conserve unnecessary run time for an entire house. If the damage is so bad that I don't have power or the ability to get fuel after a week I likely don't have a house to live in either. If I had the room I would have used a 1000 gal tank.
 
Originally Posted by FlyNavyP3
Originally Posted by Blueskies123
Have you thought fuel? How much will you need? One week, two weeks, six weeks? Where are you putting the tank? Why not a small and large portable?


I'm using a 500 gal propane tank, sized based on a week of power if we conserve unnecessary run time for an entire house. If the damage is so bad that I don't have power or the ability to get fuel after a week I likely don't have a house to live in either. If I had the room I would have used a 1000 gal tank.


Although I think your tank is plenty big enough (should give you about 200 hrs run time?), I'm in the Norfolk area and didn't have power at my house for 13 days during Isabelle and there was absolutely no damage to my house. Mostly trees onto power lines and flooding was our problem.
 
My thought for 7 days of run time was enough time to get roads cleared and be able to get additional propane delivered to the house. The tank was sized to provide 7 days of continuous run time for the entire house.

Should the situation dictate that could easily be stretched to probably double with reasonable conservation measures. In the 5 years I've been in the area and 3 hurricanes there hasn't been a storm bad enough yet that I couldn't have had fuel delivered within a week following a storm.
 
My SIL just had a Generac 22kw natural gas powered unit installed for their home. All in, I think she paid about $9K
shocked2.gif
. I lifted the top on it's cabinet to check it out. It's a large air cooled Generac V-twin with what looked like a heat trace sleeve around the engine oil filter. My BIL had to dress up the area around the unit some with some stone and edging. Per code, they have to be so many feet from the house, so you have a gas line at tripping height, etc. Luckily, they only live a few miles from us, so you know where we're going in the event of a lengthy power outage. LOL
 
I think you will be fine with a 500 gallon tank. You can always turn off breakers to things you may not need. JTK noted that his sister in law had the 22KW model powered by natural gas. With natural gas that and most other brands only produce 20KW.
 
A friend is a Generac tech and I have helped him a few times with his calls. The Generac is a vary expensive generator to have maintenance performed.
 
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