Problems with 20kw gen-set

[Toyboy]

If it requires sensing the correct RPM to open the fuel valve how does it pick up the RPM? Is there a replaceable sensor? Could be a bad RPM sensor and it won't start because it doesn't see any or the correct RPM's. When running bad output from the sensor may cause the fuel valve to momentarily shut which gives the starving for fuel symptons.

It just says "it gets an rpm signal", doesn't allude to rpm speed.

 

[Toyboy]

Pull the air cleaner and check the butterfly choke make sure it closes on start and opens on run,,, If that is working properly you have a fuel delivery issue ,, regulator's hate the cold "We had 5 call outs for this last week".. The other thing would be the fuel solenoid sticking.. A quick way to see is to tap it while the generator is running and see if it changes tune..

Just for giggles also check and make sure when it was installed it was set for NG and not Prop.. I warm weather with no load it might not show up but now that it is cold it might,,,

I took the air cleaner cover off while trying to start it, and the choke would open -close- open -close during the start cycle. Don't know if that's correct for starting or not.

It is set to NG and has successfully ran in two previous winters.

The closest Generac tech is 65mi away and it will cost me $$ for travel, $.55 mi both ways, labor and who knows what else. I've got $5k into this machine already, whats another $4-600 right. It will cost me $400 for cold weather kit w/installation in addition to above cost. I know, it sucks but whats the alternative at this point? The tech wants to see if cold weather kit will solve issue before digging deeper and costing more $$.

 

[Toyboy]

Different generator and different size but sounds like similar symptoms.

Winco natural gas generator runs rough at start up - SmokStak

Our hi here today has been -16f and I really do need to change out plugs. I'm just a little hesitant to do it in that kind of cold w/aluminum engine. The way my luck has been running this week with unit, I'd probably strip one and make things ultra bad.

 

[nc redneck]

I had a the same type problem on my RV LP generator, ended up being the regulator. Partsfortechs.com has good prices on generator parts. I also have the same whole house Generac as you do. By far one of the better things I have ever bought. Nothing like it coming on automatically at 3 in the morning. No getting up pouring gas, starting and flipping breakers, oh and watching the street light or neighbors lights to figure out when to shut it off.
For those who knock Generac I would say who needs a commercial grade generator for 40 to 50 hours per year ?
Just my thoughts.
Picture of my install.

 

[Toyboy]

I had a the same type problem on my RV LP generator, ended up being the regulator. Partsfortechs.com has good prices on generator parts. I also have the same whole house Generac as you do. By far one of the better things I have ever bought. Nothing like it coming on automatically at 3 in the morning. No getting up pouring gas, starting and flipping breakers, oh and watching the street light or neighbors lights to figure out when to shut it off.
For those who knock Generac I would say who needs a commercial grade generator for 40 to 50 hours per year ?
Just my thoughts.
Picture of my install.View attachment 353649

Which regulator. I thought the Generac tech told me that the unit also has one. Did I miss understand him?

I'm with you on not trashing not only Generac, but any other brand at this point. I have what I have, and that ain't gonna change anytime soon. I just want to get to the bottom of my problem ASAP.

If Cat made a comparable size gen-set, I would have one of them outside instead. But at the time I had this unit installed, Cat was not an option.

 

[nc redneck]

Your generator should have a its own regulator on top of supply regulator that sets inch's of water column. It is a type of demand meter that supply's gas as needed. Get a water column Gage it will help find your problem.
Demand regulators are pretty cheap, around 100.00 bucks.
I unfortunately had to pay $ 400.00 for my RV regulator as it was a safety issue. It was designed to dump any extra gas out of RV rather than to atmosphere.
My Generac has been trouble free for many years. I have not needed to tear into it.
Hope this helps

 

[grsthegreat]

i had to replace a Cat branded auto transfer switch last spring due to faulty computer board on the unit. Cost was $1,500 parts and labor. After doing lots of internet searches, i found quite a few complaints on this particular unit, and cat had redesigned future units. Mind you, they would not warranty it as it was over 2 years old (by 2-1/2 months).
The water board needing the service didnt want to squabble, and had me do the work. Just comes to show you, all brands can have failures.

after re-reading the OP's post, i didnt catch the fact that it was do dang cold where your at. that can definitely have issues with propane. Heck, my main propane tank froze up at -25F a few years back. lets hope the cold weather kit helps. I even sometimes install battery warmer blankets in severe cold units and critical care facilities.


Oh, and by the way. i ensdtall any brand the homeowner wants. I do not represent any brand. But over the years id bet 95% of my installs have been Generac (Guardian) units.

 

[nc redneck]

Good to hear from a Pro thanks for your input and common sense.

 

[Toyboy]

Your generator should have a its own regulator on top of supply regulator that sets inch's of water column. It is a type of demand meter that supply's gas as needed. Get a water column Gage it will help find your problem.
Demand regulators are pretty cheap, around 100.00 bucks.
I unfortunately had to pay $ 400.00 for my RV regulator as it was a safety issue. It was designed to dump any extra gas out of RV rather than to atmosphere.
My Generac has been trouble free for many years. I have not needed to tear into it.
Hope this helps

Earlier in these posts I did say the NG Gas Co. serviceman installed a gauge downstream of regulator. Generac book calls for 5-7" of water column and mine was set at 7". The service man backed it off to 6" to see if that would make a difference, and left gauge installed for me to monitor gas pressure when I was having trouble starting it. I did notice that the gauge would bounce back & forth from about 5 3/4" to maybe 6 1/4" when it was cranking trying to start. Whats that mean? Got me.

 

[Industrial Toys]

This Generac I installed, sounds like a freaking lawn mower screaming away. That, in my mind, is not a standby system one wants to rely on. And I must say, there is some other ugly noise from the Engine ( a briggs) , but that's not my concern.

A customer of mine has a large 150 KW genset with Cummins power and for one reason or another, that set has never worked, when there was an outage. Always performs flawlessly on excercise. Nothing is infalable, and therefore I have backups for my backups for my backups, but a 3600 rpm genset is not what I would start with. Just sayin.