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Home Standby Question

LWB250

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So now it's my turn to ask a question after years of answering them...

I'm definitely going to put a whole house home standby set in this year. I don't want to cobble something up myself, or try to find a used unit. I'm at a point in life where I can (luckily) afford to pay someone to deal with it, start to finish. Sure, I'll probably do the maintenance, but I don't have the time nor inclination to do the install or mess with finding something used. I want something new and turnkey.

Anyway, I know there are a lot of dealers around the forum that are currently servicing a number of different brands of home standby sets. I'm curious as to opinions on quality, longevity and service costs.

At present the two contenders would be Generac and Kohler. As most of you know, I worked for Kohler for many years, but that doesn't carry any weight relative to thisas I have no knowledge of their current home standby products. Late in my career I was a principal in a Generac distributor, so I know the home standby side of Generac pretty well. While I'm well aware of Generac's reputation in the industry, that's tempered by the understanding that one thing they have always done well has been consumer products.

Most likely I would be looking at a Kohler 20RESC and a Generac 7039 or 7043, running on propane with a stock 200A transfer switch.

Let me know your thoughts and opinions based on direct experience, please. I don't have any predispositions for one over the other at this point.

Thanks!

Dan
 

Steve Dawkins

Subscriber
Last Subscription Date
07/04/2016
I have been out of the game for a few years now, and don't know what is currently available. I always favored Cummins/Onan equipment, but the majority of my business dealt with industrial systems. We did install some residential Onan standby systems. Overall they held up fairly well, but a few of them had cold starting issues. These were the V-twin, air cooled, 3600 rpm units. I just checked Cummins site to see if I could provide you with a link to a home standby model that I would recommend. Unfortunately, I didn't see anything that I would consider "a cut above" everything else that's available.

If your budget allows for it, my recommendation would be a liquid cooled, 1800 rpm unit. If it's a quality machine, it should provide you with many years of service. Unfortunately, you can't escape electronic controls. As you know, one of the problems with them is that they are constantly "upgraded" with newer versions, and the one in your generator is no longer available after a few years. The trend seems to be that the engine and generator controls plus the AVR are all consolidated into one module. Whatever you decide to buy, you may want to consider buying a spare module to have on hand.

BTW, thank you (again) for your assistance with the vintage 22.5kW Kohler unit that passed through my hands a couple of years ago. Your suggestion of contacting one of the legacy Kohler dealers (TAW) for information was extremely helpful.
 
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len k

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Last Subscription Date
12/12/2018
I'don't install or on work on other people's gens. But I'm a old mechanical engineer, designed stuff that went in mil defense stuff that fly. Guys here like old Onans like 7.5kw JB and 15kw JC.

I have a JB , the windings look pretty well designed, and bonded together so they don't chaff. I'm not fond of electronic governors or complicated transistorized controllers. Have extra failure modes, thermal, electronic transients, vibration . More complicated electronic controllers give more opportunity to for component failure just to to shear number of them......think integrated circuits.

The electronic AC voltage regs on JB , JC seem to fail because of dirty pots, maybe the caps. Seems simple solution might be to just replace it if want higher reliability. Maybe just keep a spare around if it fails. Not hard to replace

I don't know Kolhler. But I picked up a free newer 5.5 kw Generac small screamer to fix and sell. Stator windings were not well bonded together, looked like could chaff. I'm guessing that's one reason I read they die so often. Mine had low hours but a dead oil pressure switch and snapped pushrod. Poor design allowed pushrod guide to rotate and rub on pushrod till it wore and snapped. I'm GUESSING bigger Generacs are designed to the same low quality /cost standards. People here say Genrac have a high failure rate, (low MTBF).

I think the old stuff was made better and simpler, so might have lower failure rate. My Onan JB looks pretty well designed and reliable to me. Bonus is at 1800 rpm they are more quite. People here seem very happy with them, no real problems. Maybe because in today's dollars a ` 7.5kw Onan JB would be ~ $7000 and it looks built like a tank., very rugged
 
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LWB250

Registered
For what it's worth, I started out in this industry almost 40 years ago working for an Onan distributor. The J series units were current products at the time, and I serviced many of them and have a deep understanding of their reliability and longevity. That being said, they're not suitable for a home standby for me, as they don't have the required capacity. You can say the same for the Kohler 7.5R/L654 units, but again, they're of no use to me as they would be far too small.

Just to reiterate, I'm not interested in buying a used/old unit. I could easily do this myself and get a commercial set, but as stated previously, I have neither the time nor inclination to do so. I'm also going with a whole house system, so we're talking 20kW or thereabouts with the loads I have (2400 SF house, 4 ton AC, etc.)

I realize the consumer grade stuff has it's drawbacks, but I'll roll the dice just to displace the risk onto someone else.
 
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Mark Dieckmann

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I work for a Kohler dealer as a service, install, sales guy. My primary job is an electrician. Since we are also a HVAC and plumbing contractor, I handle all aspects of the install work. We primarily deal with air cooled residential units and a few liquid cooled light commercial units. I also service a lot of Generac units. They have a dealer in the area but he will not service any unit he didn't install. You can get good service from either brand. I would lean towards whichever has a good trustworthy dealer to serve you. The Kohlers are generally heavier by about 100lbs in the 20kw size. Gereracs in my opinion have a better fit and finish, whereas the Kohler is a bit more difficult to work on and install. For shear durability the Kohlers extra weight and proven engine is probably best the only downside is of course the controller. I have had to replace a few. The liquid cooled RCL units are good as well and very quiet. Not sure what your budget allows
 

LWB250

Registered
I work for a Kohler dealer as a service, install, sales guy. My primary job is an electrician. Since we are also a HVAC and plumbing contractor, I handle all aspects of the install work. We primarily deal with air cooled residential units and a few liquid cooled light commercial units. I also service a lot of Generac units. They have a dealer in the area but he will not service any unit he didn't install. You can get good service from either brand. I would lean towards whichever has a good trustworthy dealer to serve you. The Kohlers are generally heavier by about 100lbs in the 20kw size. Gereracs in my opinion have a better fit and finish, whereas the Kohler is a bit more difficult to work on and install. For shear durability the Kohlers extra weight and proven engine is probably best the only downside is of course the controller. I have had to replace a few. The liquid cooled RCL units are good as well and very quiet. Not sure what your budget allows
Thanks, Mark, this is exactly the sort of information I’m looking for.

It has been my experience over 20+ years in the business, working for Kohler both at the factory as well as in distribution, that while they build solid stuff, they’ve never really done well in the consumer world. I’m sure the engine and alternator on the Kohler set are probably more robust than the Generac, but the controls are probably marginal and expensive to repair/replace.

I was also a principal in a large Generac distributor that sold a lot of home standby sets, and they did well. As Generac is more of an engineering house than a manufacturer, their products aren’t as robust as Kohler but they’re often better engineered. The consumer stuff is really where they shine as a result.

Given the choice, I would prefer to go with a small commercial unit rather than a consumer one, but I’ll have to see if the budget will support that approach. I don’t have any qualms about the air cooled products, but longevity is a concern with any 3600 rpm system.

Again, thanks!

Dan
 
For air cooled HSB, Kohler and Briggs would be my primary picks. The Kohler controls are solid since they updated to the current blue boards, Briggs boards are solid, Generac Evolution controllers had the highest failure rate, Nexus controls being a close second.

Kohler engines are nice since they run hydraulic lifters, so no valve adjustment needed. Briggs engines had about an equal failure rate to Honda (almost none). Briggs also has the best HSB load management system (Symphony) on the market if that's something you'd be looking at.

The older square bodied Generac HSB units last forever and are pretty much bulletproof. The modern stuff is hit or miss. Had some that went years without issue with only basic maintenance, some that would spit main seals out after the first few excercises, and some that would spit a rod out of the side of the block in the same timeframe.

Generac EcoGens had the highest failure rate; brushes chewing through slip rings and destroying the rotor, plastic oil makeup check valves getting brittle and breaking off, and controllers not shutting down on low oil and continuing to run the engine dry.

Just some random observations I've collected over the years working service for dealers in Generac, Kohler, Cummins, Briggs, Milbank, Winco, and fixing anything else that pops up.
 

m_thompson

Registered
I will also buy a home standby generator this year, so this discussion is really useful. There are lots of Generac units in my neighborhood. I don't mind spending a little more and get something that is really reliable.
 

LWB250

Registered
For air cooled HSB, Kohler and Briggs would be my primary picks. The Kohler controls are solid since they updated to the current blue boards, Briggs boards are solid, Generac Evolution controllers had the highest failure rate, Nexus controls being a close second.

Kohler engines are nice since they run hydraulic lifters, so no valve adjustment needed. Briggs engines had about an equal failure rate to Honda (almost none). Briggs also has the best HSB load management system (Symphony) on the market if that's something you'd be looking at.

The older square bodied Generac HSB units last forever and are pretty much bulletproof. The modern stuff is hit or miss. Had some that went years without issue with only basic maintenance, some that would spit main seals out after the first few excercises, and some that would spit a rod out of the side of the block in the same timeframe.

Generac EcoGens had the highest failure rate; brushes chewing through slip rings and destroying the rotor, plastic oil makeup check valves getting brittle and breaking off, and controllers not shutting down on low oil and continuing to run the engine dry.

Just some random observations I've collected over the years working service for dealers in Generac, Kohler, Cummins, Briggs, Milbank, Winco, and fixing anything else that pops up.
Great information! Thank you!

Dan
 

len k

Subscriber
Last Subscription Date
12/12/2018
If you get a new gen that is not that reliable, I'ld also install an old Onan as a backup to it that you can depend on. Even if you have to load manage to do it. My Onan is primarily to power oil furnace for heat in winter.
 

LWB250

Registered
If you get a new gen that is not that reliable, I'ld also install an old Onan as a backup to it that you can depend on. Even if you have to load manage to do it. My Onan is primarily to power oil furnace for heat in winter.
Len, you're missing my point. I'm looking to simplify, not make things more complex. I certainly don't want a backyard full of iron (or aluminum, for that matter.)

Thanks.
 

LWB250

Registered
Not a problem! Feel free to ask anything else that comes to mind and I'll see if I can help.
I'm going whole house, so load management isn't an issue. I'm beginning to think that Kohler is the way to go.

I've got people coming out over the next week from both Kohler and Generac to give me estimates. I won't reveal my background to them so as not to color their opinions or approach to quoting me. I expect I'll be looking at the 20kW air cooled models in both with a 200A ATS.

This should be interesting, and I'll be sure to report back. The Generac folks are coming tomorrow, the Kohler people next week at a time yet to be determined.

Dan
 

Mark Dieckmann

Registered
Dan, you're right about the Kohler engine and alternator being robust. Marshall is correct about the newest blue board controller. They seem to be better than the previous two versions. When comparing commercial units, be aware that most Generacs are still 3600rpm and loud. The Kohler RCL's are 1800 and nice and quiet though pricey. They use the same controller as the air cooled units, so you can't get away from it. It will be interesting what you learn.
 

LWB250

Registered
Thanks for that insight, Mark.

As much as I would like to go water cooled/1800 rpm, I'm not sure I'm willing to pay the premium for it. Looks like a water cooled 20kW unit would be nearly double the price of an air cooled one. Ouch. That's a significant premium.

More as I know it.

Dan
 

Wayne 440

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I am not in your target demographic for opinions. That said, IF I needed 20kW from a gaseous fueled set for my home, I would likely buy a Kohler 24RCL. It is about $1200 less costly than the 30 RCL with no turbocharger to deal with, and I'm pretty sure that the "Kohler" engine is actually a Toyota. The cost is still north of $10K, but there are few things more frustrating than a standby generator set that doesn't work when needed. You are buying a device that you will expect to use for a number of years, the added upfront cost will be less painful if you think of it as a yearly cost for having a more capable system.
 

LWB250

Registered
Points well taken, Wayne, and certainly something I’m considering. I haven’t totally dismissed the idea of a water cooled set, I just need to get a handle on exactly what I need and what’s offered.

I would probably expect to amortize costs over a 20 year period when looking at the numbers. That softens the blow somewhat when you work it out to an annualized cost.

Thanks!

Dan
 

Birken Vogt

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I work on all of them and my background is engine mechanic/electronics tech.

In my opinion Kohler wins in almost every way. Engine first, they know how to make an engine and sell it to third parties. It has hydraulic lifters. The controller, while expensive, does not have the failure rate of some others and the potting, etc. is obviously more robust. Probably why it is expensive. Other thought went into it, such as 1000 events in history instead of just a few. Programmable exercise duration. Brushes accessible is also a nice feature. You are allowed to do your own firmware updates if you are into that sort of thing. RXT load shed system works very well and does not rely on waiting for the engine to choke before activating.

I think their fit and finish is better especially lately.

Warranty compensation is fair for the dealer, big plus.

Big selling point right here: They are the only air cooled units that go the distance in off-grid service. Everything else seems to wind up on the junk pile right quick.

I agree go with liquid cooled though if you can afford it. One thing we are learning here in California is they all (3600 rpm) need the oil checked on a daily basis when these outages go on for a week at a time.
 

LWB250

Registered
The Generac guy was here. He was pretty thorough, but I will say that I question some of the sizing. I've got a 2410 SF home, 4 ton AC unit, electric (hybrid) water heater and electric stove and dryer. I would likely not be using the dryer or stove during an outage, but I did ask him to size for whole house operation. He was telling me they will probably use a couple of load shedding modules, at least one for the AC. I was a little surprised by this, as with a 22kW air cooled unit I wouldn't expect a 4 ton AC unit to be an issue.

Hmm.

For what it's worth, he said a water cooled set would be roughly $6k more than a comparable air cooled set.

Waiting on a date and time for the Kohler guy to come by.

Thanks again to everyone who has weighed in on this. It's been helpful, even for someone who was in the business for 25 years...

Dan
 

LWB250

Registered
Generac quote is in.

Either I've been out of the business so long I've totally lost any idea of costs, or things are out of control...I've researched costs for equipment, and I certainly expect a markup if someone else is supplying it, but...

Here's the deal in summary:

Generac 22kW 7043
Concrete pad, permits, delivery, setup, etc.
2 - 120 gallon upright propane tanks and related piping, tanks will be filled
95' run of cable from generator, trench 10' then along an exterior wall to transfer switch inside garage next to distribution panel
200A ATS
Startup, battery, etc., etc.
5 year warranty

$14,300.00

So in this case it would appear that the installation is going to be pretty much equal to the cost of the generator set. I can't recall when the install was equal to the equipment cost. I certainly saw plenty of times when it was easily half, but 100%? This is in a standard residential home, nothing unique or unusual about the location or siting.

This may color the way I go at it with the Kohler dealer. I may tell them I'm supplying the fuel tanks and piping. The Generac guy alluded to this being a major cost these days.

Comments?

Dan
 
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