Battery goes dead on my home Generac generator

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Gosh
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Tue Sep 10, 2019 6:53 pm

I have a 12 kw GT990 Generac Centurian Generator as a backup for my home. Serial Number 5339329. I purchased and had it installed from Lowes in 2012. The only issue I have ever had with it was the control panel LED screen went blank, or maybe more descriptively burned out, about a year into my owning the unit. However, the unit still worked normally, I just could not change anything because I could not read the monitor. I do a oil change maintenance on it each year. I noticed it had not been doing it's weekly 15 minute test about 6 months ago. I discovered the battery had gone dead. This was the second battery in the lifetime of the generator and had been in the generator for at least 2 years with everything running fine. I purchased a new battery and the unit fired up fine and I thought I had fixed the problem. It took me about 3 weeks to notice it was not working again and discovered the new battery was dead. I tried to charge the new battery but it would not hold the charge. Fortunately the store honored the battery warranty and I have a new battery. But, I am afraid to install it only to have this one discharged as well. It appears to me I have a problem somewhere in the generator that is causing my battery to discharge but I am not really sure where to begin looking. i have a good Sperry voltmeter, but, I am not real knowledgeable in its use or the language of Ohms, Amps, volts, watts, etc. Please help.
Chris
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Tue Sep 10, 2019 7:17 pm

This is most certainly a bad battery charger.

You'll find a charger in the transfer switch which you can see here: https://shop.gentekpower.com/products/g ... connectors

It was fairly common for the older versions that came with them to fail...
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Gosh
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Fri Sep 13, 2019 9:26 pm

Where can I find the transfer switch?
Chris
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Fri Sep 13, 2019 10:20 pm

The transfer switch is the main box that transfers power from utility to the generator. It may be time to call your local Generac dealer in for some help.
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
Gosh
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Sun Sep 15, 2019 9:09 am

Found it. Thanks.
Chris
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Sun Sep 15, 2019 10:23 am

I'm glad to hear it! Just make sure when changing the charger out that ALL power is off to the transfer switch. That means the main house power and the generator are both off and confirmed dead with a meter. The transfer switch has live 240V inside.
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
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