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stnbenn
January 7th, 2009, 02:44 PM
I hope this posts as I went through a lenghty thread posting then it wouldn't allow it for some reason. I was able to copy it and will attempt to paste it here. Stan

EDIT: Looks like it's gonna work this time. Here is my initial post:

Hi guys, been visiting the site and gathering info for a couple weeks. Great place to find some answers and hope I can get my problem resolved. Bare with me as this will be a long initial post to give you background info on this unit and my problems to date. I apologize for being so long winded, but want to be as thorough and informative as I can.

I bought my 12KW Generac model# 04456, S# 3615530 complete with 100A. automatic transfer switch on March 24, 2007 from our local Home Depot store in Benton Harbor, Mi. This unit was a floor sample, display model that was like new and never sold or installed. I got a great buy at just over $1800.00 inc. tax out the door. It had sat there on their floor for at least 2 years that I know of. They had lost all the manuals but I was able to download what I needed (I thinK). It has taken me a long time to get this unit hooked up as I went though a lot of trouble simply trying to find out the correct size of Polyethylene pipe required for the 200 ft run from my 500 gal. lP tank, and then trying to buy it without being a HVAC contractor. Finally got the maintenance planner from my former employer to get it for me. He took 2 months and a lot of calls, and dragged his feet. Lot's of varied and differing opinions about sizing from everyone including Service guys, friends, doofus's who didn't know JACK, suppliers and experts. I decided to go ahead and do the electrical part of the installation, and get back to the gas problem later.

About July 2007, I installed the generator on the supplied plastic pad on top of a 4" poured concrete pad and anchored the unit. I drove a new ground rod to ground the cabinet, installed the transfer switch in the basement next to the main panel, installed a new 70 A. breaker in the main panel to feed the transfer switch, and wired all the conductors and control wires interconnecting the switch and generator except for the neutrals as this was not really clear in the instructions of the manuals that I had downloaded. I was aware that these were supposed to be floating neutrals, and in further searches on the internet I found info that advised to simply pigtail the branch circuit existing neutrals to the ungrounded neutral bar in the transfer switch. I was hesitant about pigtailing neutrals, (just goes against all my training and thoughts) however I was motivated to get this generator hooked up and in operation. I never did much work on generators while I was still working, and always preferred grounded neutrals in any hard wired circuits I designed. (By the way, I'm a retired liscensed electrician from the Whirlpool corp. here in St. Joseph, Mi.) No that don't make me any smarter about these units.:o


In September 2008, I installed a new high pressure (10 psi) regulator at the 500 gal. tank, and transitioned the regulator to the 1" black pipe, shut off valve, test port tee, and fittings run underground appx. 10' to connect the pipe to the Plastic tubing using the necessary (and expensive) transition fitting to the Poly pipe. I also transitioned back to 1" black pipe within 3' of the low pressure regulator (11-14"wc) at the generator. Here at the generator area I bell reduced the 1" black pipe to 1/2" and installed a 1/2" shut off valve just before the regulator. I installed the 3/4" flex pipe that came with the generator, from the regulator to the generator. A 24 hour pressure test at 15 psi was fine and no leaks.

After reading lots of horror stories about this and that pertaining to warranty issues, I decided to contact a Generac service tech to do the initial start up. This young fella is an electrical contractor and when contacted was eager to do the work. When he arrived a few days later he informed me that I needed to get the necessary warranty info in to Generac in order to make the warranty legal. (I didn't know what the warranty requirements were due to no manuals or info. from Home Depot) I downloaded the warranty form and sent in all the info to Generac in October) The service tech made some checks to my hookup and noted that everything looked fine. He changed the fuel connections on the unit, to run off LP and we started the generator for the first time. The engine ran but surged and he thought it might be the govenor setting. He tried to adjust the LP screws a little and no change. He was not able to remove the test port plug to verify correct fuel pressure. With the engine surging he checked the voltage from the generator and noted only about 21 volts. He tried to adjust the voltage regulator but not much help. At this point he had been here about an hour and said he thought the stator was at fault, but he had to leave and go to a seminar at Generac in Whitewater, Wi. the next day and would get back to me next week. After 3 weeks I called him and asked if he had any intentions of coming back to work on the unit. He said he'd been busy but would be back next week. That was 3 weeks ago and i've given up on him. I will not call him back, nor pay for his initial service call. He didn't seem to know much more about this unit than I did. I had tried to contact another dealer and service company locally several times by phone, cell phone, and website but never got a response. Won't call them again either. Seems the so-called techs are fat and sassy here in this neck of the woods and don't need the work. (might come back to haunt them in this economy).

After giving up on this guy, I started the generator up last week and the WALAAAA, the engine seemed to run pretty smooth. No surging like when we first fired it up. Magic I guessed!!! I shut it down and strutted around a while.:D

After reading here of low voltage output from the generator, I checked mine and only had about 3 Volts on cranking. I excited the field as Kelly outlined in some other threads and the generator started genning to about 17 volts. ;) Following the initial startup instructions in my manuals and with generator breaker off, I used my Fluke T5-1000 and noted about 350 volts across L1 and L2. I adjusted this down to 250 V. and after some more strutting, put the unit under load one breaker at a time. Worked fine carring the lights, 2 reefers, and a 3 ton heat pump and furnace blower. Finally after about 15 minutes of purring along nicely, the heat pump satisfied the room thermostat set temp, the heat pump shut off as it should, and immediately the engine started to surge. This created a kind of brownout condition, I took a quick voltage reading and it showed about 60-80 volts instead of 240. I immediately threw on the main 225 A. breaker to take the generator off line. The engine continued to surge and did so even on manual with breaker off. It continued to surge with no load applied. I finally shut it down. I then started it up on manual, and it still surged.

After an hour or so of being back on the grid, I noticed that the furnace blower would not come on thought the heat pump compressor came on. When I switched over to the LP furnace, it would light up and after no main blower action, would shut off for high plenum temp. The brown out condition must have burned out the blower relay. That was replaced by my local HVAC guy for $165.00 including service call, and today I got my nerve back enough to try again.

I followed the instructions again to the tee, applied load through the individual transfer switch breakers and again as soon as the heat pump shut off, the engine started surging, but not as severe as before and this time the voltage that I (quickly and nerviously) checked was at about 200-240V. I immediately threw on the main breaker and the engine continued to surge. I went outside while the engine was running with no load and noticed that the govenor spring was a little loose(no tension on it from the linkage). I took hold of the linkage as it was surging and didn't help, put tension on spring and no help. I noticed no alarm lights at all. I then shut it down.

Now all that said, I do not have a freq. meter so can't check or set engine speed even if it might be off spec. I can't say that the fuel needs to be adjusted as there is hardly any surge at full speed idle. I don't understand why the engine starts to surge when the heat pump (the highest load) shuts off.

I also don't know who to call around here even if they would return my calls, or show up. Home Depot suggests the Generac service rep. in Kalamazoo, Mi. about 60 miles from here.

Got any suggestions? I'm open and, again, sorry for the novel.....Stan Bennett, St. Joseph, Mi.

pcfrisch
January 7th, 2009, 07:27 PM
I would go through the govenor adjustment procedure in the manual. You will need a true rms DVM.
Make sure you follow the break in procedure. It is not good to run a full load on it at first.

stnbenn
January 8th, 2009, 07:45 AM
pc, thanks for the reply. It is cold and snowey out there today so may not get to work on "Old Yeller". I noticed a thread here where someone had a similar problem with a 12KW that had a temporary surge when the dryer shut off. Can't say that my problem is exactly the same but might be similar and an avenue to explore.

Kelly, thanks for the password reset.

Stan in SW, Mi.

Dave Carney
January 8th, 2009, 08:04 AM
I'm no expert, but engines that surge under no load, and then don't when loaded, are generally running too rich. I'd check choke operation and the mixture settings.

Also, I'd check valve lash, always on these things, I don't think Generac spends much time getting that right on the money, which it needs to be.

pcfrisch
January 8th, 2009, 08:55 AM
pc, thanks for the reply. It is cold and snowey out there today so may not get to work on "Old Yeller". I noticed a thread here where someone had a similar problem with a 12KW that had a temporary surge when the dryer shut off. Can't say that my problem is exactly the same but might be similar and an avenue to explore.

Kelly, thanks for the password reset.

Stan in SW, Mi.

What Dave said too. It probably could use a full tuneup. Fuel causes a lot of problems.

stnbenn
January 8th, 2009, 06:26 PM
The service kid did monkey around with the fuel adjustment screws, so I might try and work on that and see what happens. Will have to read the manual to see what is correct way to adjust the mixture.
Thanks for all the help so far. Will see what I can do tomorrow if it isn't too cold, though its supposed to get into the teens tonight. Funny, when I had snowmobiles the cold didn't bother me as it does now. Couldn't be that i'm getting too old to play in the snow, or could it?:o
Stan in SW, Mi.

WDedic
January 12th, 2009, 01:38 PM
Check for loose Neutral Wire at the generator and in the transfer switch.

stnbenn
January 16th, 2009, 01:30 PM
Dave, looks like that the problem of surging after removing load was as you suggested, improper fuel adjustment. I followed the instructions for adjusting the fuel adjustment screws, and now for the first time since I bought this unit 2 years ago, the generator is working. I still have a problem with the speed as I see it. I can't get over 59.2 HZ with no load and loaded about 57.5. Guess I might have to adjust the govenor in order to increase the engine speed and bring the frequency up to 61-62 HZ on no load. It was only about 10 outside so had to come in and warm these old 65 year old hands a couple of times. Can't seem to work with gloves when i'm trying to feel the adjustment screws. Like trying to tap dance with snow shoes on.:)

I thank all you guys for the most helpful information on my problem and for the suggestions for the recommended diagnostic meter. I did a lot of reading of posts here before I registered and started posting. You can never go wrong, if you "ask someone who owns one". This is a great site and I will continue to monitor and post if I have anything to help anyone else. A big thanks to Ziller, Kelly, Brian, and all others who help the dummies like me.

Stan in St. Joseph, Mi.

Dave Carney
January 19th, 2009, 04:53 PM
Cool.

Yeah, frequency is just rpm divided by 60, so your rpm is about 150 under ideal.

stnbenn
March 10th, 2009, 12:34 PM
This is just a followup post to the problem I was having. (thought I had done this before going to Florida for 5 weeks).
Only after Skip, Dave, John and some others set me straighht on what meter to buy and suggested adjustments for the engine surge, I was able to set the frequency as per instructions and she runs smoothly now. This was simply a fuel mixture adjustment, and a mechanical adjustment with the linkage to increase the speed of the engine to reach the required frequency. The generator works pretty well now for supplying the circuits I have chosen as emergency. I decided that the heat pump was just too much of a load for this 12KW unit along with the 2 reefers, well water pump, lights etc. that I had chosen. I now just use my LP furnace as primary heat source during any power outages. This takes care of any potential brown outs when the heavy load of the heat pump compressor, the exhaust blower and main blower of the LP furnace tries to start. I installed an hourmeter (on the transfer switch door) to monitor the running time and I also record the reading to be sure that it is exercising when i'm away. So far so good. I'm also installing a 300VAC analog panel meter to monitor voltage when the unit operates.

I feel more confident now that this 12KW unit will serve my basic needs. If I knew then (when I purchased the 12KW unit), what I know now from all the help I recieved from you folks, i'd have opted for at least a 17KW, and maybe a 20KW unit. Thanks again all for all the help, and all the folks at Ziller for providing the space to swap information.
Stan in SW, Mi.