Need advice: Onan vs. Generac Q55-G?
Rudy
4KW Emerald or the Generac Q55-G? They are about the same price, but
I've heard the Generac will outlast the Onan and uses about half as
much fuel to operate. Would appreciate any pros and cons. Thanks.
Robin
My choice would be the Generac. This is the bottom line at top. Ha.
I had an Onan 3.5 kVa 3600 rpm in a Class C motorhome, and now have an
Onan 5 kVa 1800 rpm mounted on a trailer for amateur radio use and house
backup, and a Generac 5.5 kVa in our fifth wheel which runs at about
2100 rpm.
The Onan Emerald is an 1800 rpm machine so it should have a decent life
span.
The Generac I have is a constant speed machine, about 2100 rpm for the
engine and 3600 rpm for the alternator. This is a good arrangement
since alternator speed has little effect on wear. So my Generac should
have a comparable life span.
But, I understand the Generac Q55-G has a variable speed arrangement
based on load but still puts out 60 cps. So this should make for very
long life and somewhat reduced fuel consumption. Most RV generator load
is a toaster, microwave or coffee maker. So the Generac probably would
not run much above its minimum speed except when running an air
conditioner.
The company I worked for had Kohlers and Onans at remote transmitter
sites. These ran about 3 hours a week unless a power outage occurred,
then they ran continuously. The Kohlers required new rings about every
10 years. The Onans seemed never to wear out.
I don't think wear is much of an issue with an RV generator unless you
plan on a heck of a lot of boondocking.
It would surprise me if there is much difference in fuel consumption
between the Onan and Generac you are considering.
Weight is not an issue. Both generators you are looking at weigh the
same.
The Onan's rated sound level is 77 dBa at 10 feet in the open. The
Generac is rated 67.1 dBa installed at 50% load. 77 dBa is nearly ten
times noisier than 67.1. Since the criteria are different for the
ratings it is difficult to determine the true difference in noise level
when installed. But I would strongly suspect the Generac is the
quietest. The variable speed feature should contribute to this.
The Onan has a 4 kVa rating, the Generac 5.5. The extra 1.5 kVa could
be useful. Altho I did run a 13.5k air conditioner with the 3.5 kVa.
I have not seen a Generac Q55-G but it probably has a 3600 rpm
alternator. This is a plus that is not readily apparent. The high
speed alternator has a lot of rotating inertia so it can "snap up" a
heavy motor load such as an air conditioner when you have other load
running.
All this adds up to my choice being the Generac.
You have a fair amount of work ahead of you to install either.
BTW, I later converted the Generac to propane. Big mistake. It uses a
LOT of propane. This is not unique to my machine. I've read the
consumption figures and mine is consistant with others. I would not
recommend anyone getting a propane powered generator unless they
intended to use it infrequently. For my use, the negatives outweigh the
positives. But, infrequent use is where propane power does stand out
since there is no liquid fuel to get old and gum up.
Recently we got an Onan 7.5 kVa Diesel generator to replace the Generac
which will replace the Onan 5 which I'll dispose of. The Onan Diesel is
extremely quiet and fuel useage is really low, about 0.13 gallons an
hour at light load. Since our tow truck is a Diesel with an aux fuel
tank, I can transfer fuel easily. Major negative: price.
Hope this helps.
Bob KU8C
Mike Niemela
Now that was an interesting post!
Best
Mike N
Robin
Thanks. Now if I could only get myself to limit posts to 100 words max.
By golly, I think I'm doing it this time!!
Bob
Mke Christenson
to get manuals for it. They were very courteous and helpful. We received
the manuals and authorized service center listing at no cost even though the
unit was way out of warranty.
It is my understanding that the Onan does not have a pressurized oil system.
The Generac does. I feel this feature alone will definitely add to the life
of the unit. The Q55 is rated at 0.15 gal/KWH. I don't know what the Onan
is rated at. Possibly someone could supply that figure. The belt
components that turn the generator are warranted by Generac for the life of
the unit.
The Onan, however, is much more popular and as such parts and service will
be more readily available.
HTH,
Mike Christenson
sys...@ktc.com
Rudy wrote in message <36e15481...@news.alt.net>...
POLLOCKB
that he handles both Generac and Onan, but that the Generac will far outlast
the Onan. He said that he has Generacs that have more than 20,000 hours on them
and they are still running well. When they get up to 15-20,000 hours, he often
has to replace a couple of bearings in them, and then they go on. I live in
Southern California, and he watches over a fleet of trailers and 5th wheels
used by the movie industry. Apparently, the trailers go to a remote filming
area for weeks and months where the generators run 24 hours a day serving film
crews who don't really look at the trailers as their own personal investment.
Hard on the generators, but the Generacs just keep on performing. He was very
emphatic that I should expect to get 25,000 hours on the generator. Unlikely
that I will ever accumulate that many.
Robin
>
> We have a Generac NP52G in our MH and like it. We contacted Generac direct
> to get manuals for it. They were very courteous and helpful. We received
> the manuals and authorized service center listing at no cost even though the
> unit was way out of warranty.
>
> It is my understanding that the Onan does not have a pressurized oil system.
> The Generac does. I feel this feature alone will definitely add to the life
> of the unit. The Q55 is rated at 0.15 gal/KWH. I don't know what the Onan
> is rated at. Possibly someone could supply that figure. The belt
> components that turn the generator are warranted by Generac for the life of
> the unit.
>
> The Onan, however, is much more popular and as such parts and service will
> be more readily available.
>
> HTH,
>
> Mike Christenson
> sys...@ktc.com
>
Mike,
I have had a couple or three Onans apart including an Onan engine on a
railroad speeder car and for the life of me can't remember if there was
an oil pump or not. But I do remember they had a screw on oil filter
which would appear to require a pump. And I seem to remember a low oil
pressure shutdown but may be wrong about this.
The Generac has a vee twin B&S engine which is used on a lot of
equipment so parts should be readily available. We have the same
generac you have which I converted to propane. The oil never gets dirty
from one yearly change to the next. Uses a lot of propane, tho.
Bob