I have installed a 16kW standby generator and I am having a problem with the furnace. It is a 10kW furnace and the rest of the generatoris running lights, outlets and a well pump. When the generator starts, everything is fine. Then about five minutes with the generator running, it trips the 65 Amp breaker inside the generator housing. I can run the lights, outlets and well pump by itself with no problem, but can't run the furnace without shutting down the generator. The furnace is 240V on a 50A 2 pole breaker. It will not trip this breaker. The generator main is a 70A breaker. This is the third one I have installed. The other two have no problems. Could the 65A breaker be faulty? Please help. Thanks, I have been looking at different questions on this site, and I have liked what I have seen so far.

An Amprobe clamped around 1 of the wires will show actual Amps drawn.
You may have too much of a load. I would check draw of each item.

Please provide the make and model number of the genset.

Stratmando, I am going to do that on Mon. I don't think that it is too much load though. The gen. was on a 50A breaker to begin with (in original distribution box). I will check each load and let you and tkrussel know them. Tkrussel, the generator is a generac (guardian) automatic standby generator. I have installed two other generators and no problems with either of them (both 7kW same company). Thanks for both of your responses.

I switched the wires in the main breaker for the generator, and that worked. The system runs at 46A FL. I was there for an hour and ran the system on just generator power with no problems except when I started to take readings on the system and turned off the generator main breaker. The system was running off the generator only and the generator continued to run and supply power! I will say that this problem was detected before I switched the two wires in the generator main. I turned off every breaker in both boxes (not the one in the generator enclosure) and still had power. I had no voltage across the lugs on the breaker, T1 & T2 to ground 97 volts, T1 & T2 to main lugs on the generator panel 107 volts. Any ideas on what to check? I do not want to leave this like this for safety reasons. I will explain anything you do not understand. Thanks

rknopp... do you have a transfer switch installed?

Yes, sorry about not putting that down. It is an ATS (auto transfer switch) A couple of links that may help with pictures (one is a PDF)

http://www.guardiangenerators.com/pu...0174210SBY.pdf

GUARDIAN 16kW

Thanks for your response Cobraguy.

I am having a problem understanding which breaker did you switch the wires? And Line or Load?

I am assuming you are referring to the Generator Output breaker, but I do not see T1 or T2 in the wiring diagram. Are you measuring the voltages at the Line of this breaker?