Quietpact 75D Loses voltage when hot

Generac, Guardian, Honeywell, Siemens, Centurion, Watchdog, Bryant, Olympian & Carrier Liquid Cooled Home Standby & Commercial generator troubleshooting and repair questions
Post Reply
bduemig
New Member
New Member
Posts: 2
Joined: Sun Jun 19, 2022 9:39 pm

I have a Generac Gardian Quietpact 75D Generator in my 2004 Motorhome. It is fueled by diesel.

When it is hot outside and after the generator has run for some time with the A?C Running, AC voltage drops out . In a few minutes, it starts back up and shuts down AC again. It may do this 2 r 3 times then will not attempt to apply voltage until gen set is shut down and restarted.

I checked coolant and it is good. Someone suggested that the voltage regulator is overheating. After seeing the price and reading that the excitation CB rests in about 2 minutes. I am thinking about changing both. Is there any checks to the voltage regulator and excitation CB to verify which is bad if either?
Chris
Site Admin
Site Admin
Posts: 5688
Joined: Sat Aug 04, 2018 8:46 pm
Location: Clawson, MI
Contact:

You could confirm whether or not its the excitation breaker by checking for continuity through it when the power output dies. You'd have to do that with the unit off. You will also hear a faint 'click' when the circuit breaker is resetting.

You should also confirm voltage output is normal when it is making power. If it's higher than expected, the DPE breaker will trip.

The DPE breaker is a thermal type breaker, so if it's overheating in the enclosure for some reason, that may be adding to the problems.
Generac tech for over 12 years. I'm here to help!
"The only source of knowledge is experience" -Albert Einstein
Looking for Generac parts? Gentek Power offers the full line of Generac replacement parts! Shop Gentek Power Generac Parts
A list of my favorite Generator & Electrical Tools! https://www.amazon.com/shop/gentek_power
bduemig
New Member
New Member
Posts: 2
Joined: Sun Jun 19, 2022 9:39 pm

Thank you. I will be working on n it next week. I will post the results.
Post Reply