Those w/ Generac stanby generators....quick ?

[General Lee]

I have a 20KW, recently installed. I have noticed during exercise mode it sounds as if the exhaust or motor has a small miss. It runs at a lower RPM during exercise mode (normal) The miss, (slight popping sound) is really only heard up close to the unit. The further you are away you can't hear it. And the miss is only every few seconds.

Is this evident on any of your units? Is it normal? I was thinking it may be the governor doing its thing to control the RPM's. Trying to decide if I need someone to come out and take a look.

 

[mfreund]

I have a 20kw on propane. I have not noticed any type of miss. Ours also runs at full throttle when in exercise mode. I wonder if yours is set properly for the fuel being used. If you take off the air cleaner there is a rod in the middle of the carburator that needs moved for propane use. It comes from the factory set for Natural Gas.

It is the best money I have ever spent

 

[dschuffert]

I have two 20KW units that run on propane. I run them at a lower rpm in exercise mode. I do not notice any type of miss. I installed mine in April of this year and exercise them on a weekly basis on Saturday mornings. I just installed the cold weather kit in each one this weekend. I ran them in manual mode for a few minutes to make sure everything was still working after I installed the kit.

As mfreund stated you may want to check to make sure the fuel type selection is properly set. You may also want to check and test weather you are getting proper gas flow as described in the manual.

 

[kiotiken]

I have a 16KW unit and it runs a lower RPM while exercising. I notice the exact same thing you do. It's been doing it since new, which was several years ago now. It's never missed a beat when needed.

 

[Toyboy]

I have the 20kw and have the pop in the exhaust from time to time when in exercise mode also. Mine is running NG. To me it seems like it may not be burning cleanly and sending some unburned gas into exhaust. Maybe it's because it's running at a slower RPM??

 

[BuzzardA91]

I have the 15kw portable generac ultra source. It ran lousy from brand new as well as had a slight leak when hot ( one or two drips on floor ). Generac is the WORST company I have ever dealt with. With a few hours on it Generac gave me where to bring it to. They also said a few jobs is acceptable. Keep in mind generator weighs 500 pounds and is no pleasant to transfer. I arrived and found their repair center to be somebody's house and got no answer. Called Generac and they sent me somewhere 55 minutes away. They looked at it and said I was using too high a grade gas and drop to 87 because it was running too rich. Made sense to me. Lost power for 10 days a year later. Ran like crap and brought it back. This time they said I'm not using enough of the power of the generator and the extra gas is burning off causing the pops. Made sense I guess. Hurricane Sandy came and was out for four days. Loaded it up, still ran lousy.

Now it's off warranty with under 100 hours. Paid my local non-generac shop to check it. Very quickly they found the bolts that attach the carb to the manifold were drilled off kilter. This cause the carb to not sit flat and was sucking air causing the popping and lean conditions. $50 for a new manifold plus labor. Thanks generac.

Good luck dealing with Generac but maybe check that first.

I bought a Honda a few days ago. I need it to run when I need it. The popping in mine got worse with time.

 

[General Lee]

Interesting that a couple of you guys are hearing the same. Mine is propane and is set to propane. I physically saw the tech make the switch under the air cleaner. Plus it was originally set to NG and didn't start right away before he realized to switch it over.

When we tested it after install it ran absolutely fine at full throttle and it hasn't run full throttle since. There hasn't been any power outages, so the automatic weekly test run is all it has done. My neighbor has the exact same set up and I don't notice the slight miss/pop on his. I wonder if something is slightly out of adjustment. I will have to check what the proper gas flow is per the manual.

I'm not comfortable enough to throw into manual mode. When the electrician simulated a power outage he didn't do the steps what the manual calls for and I'm worried I'll screw something up doing it myself. I have the 100 amp automatic transfer switch with all house breakers except for 3.

 

[hr3]

When you put the switch in manual your only running the engine not transfering load to the house.. Try it....

As far as doing the transfer test you should do it at least once a year...

 

[Pettrix]

I have the 15kw portable generac ultra source. It ran lousy from brand new as well as had a slight leak when hot ( one or two drips on floor ). Generac is the WORST company I have ever dealt with.

I've heard that Generac has had some issues. From my research I came to the conclusion that diesel generators are the only way to go if you want reliability. I will give it to Generac that they have some pretty good sales and marketing going on.

 

[daugen]

I believe the standard setup is for the unit to run at 2400 rpm instead of 3600 rpm at test. I have had my 20kw for almost three years, gone through multiple major outages, and the unit has run flawlessly. I have not heard any misfires during the test, but haven't been very close to it to hear it well either. The unit burns zero oil, the air filter is never dirty, and I change the oil with Mobil 1 and a new oil filter every Spring. The motor compartment still looks new, and the readout, after an initial low battery issue, has read "ready to run" ever since. I agree with annual transfer switch testing; that's a big solenoid in there and it makes a pretty good clank when it moves. And you want to make sure it moves...
I really don't think you can hurt the unit; the interface is pretty smart. Just rocker the switch off auto and start it on "manual" if you wish. I do that before changing the oil every year. And btw, Wix makes a fine replacement oil filter...

I run on propane, two large bottles, and after three days of running, the fuel meter only showed a drop from 75 (80 is full) to 60, so the thing is pretty efficient for our purposes. We have an all electric house and when the heat pump kicks on, we can hear the gen groan and the lights flicker once in a while. I've now learned to turn the hot water heater off during long outages, and that has helped, as we have three fridge/freezers.
Engine starts at 9 seconds and the lights come on at 16 seconds, every single time. And so far, no odd noises. Your installer should be able to go through the test procedure with you in about two minutes. If he isn't sure, you need a different guy. And i would definitely pop off the air cleaner and look down in there to make sure the fuel switch is in the right position. Seems every Tom, Dick and Harry is now a "backup home generator" installer, after our last storm. And most electricians don't understand the propane/LNG regulator issues, so it becomes a pointing match between the installer and the gas people.