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rkurlan · 01-12-2017, 07:03 PM

Can anyone tell me if the alternator on the motorhome will charge the house Batteries when you're going down the road or do they just charge the coach Batteries

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Misty123 · 01-12-2017, 07:10 PM

Quote:

Originally Posted by rkurlan

Can anyone tell me if the alternator on the motorhome will charge the house Batteries when you're going down the road or do they just charge the coach Batteries

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For Entegra the alternator will charge both sets of batteries.

twinboat · 01-12-2017, 07:13 PM

It will charge the house ( coach ) batteries, if the battery isolation solenoid is functioning correctly. The solenoid is a common failure point.

The batteries that start the engine are called chassis batteries.

757driver · 01-12-2017, 07:24 PM

Quote:

Originally Posted by rkurlan

Can anyone tell me if the alternator on the motorhome will charge the house Batteries when you're going down the road or do they just charge the coach Batteries

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Yes, the alternator will charge the house batteries while driving but not as well as some think. When you start out driving for the day the alternator will charge the house batteries for 1 hour and then switch off. The net gain to the batteries for that 1 hour will be about 30-35 amps. The charge to the house batteries will remain off until the house batteries drop to 12.6v or less and then charge again for 1 hour. This cycle will continue for the driving day.

Unless you drive a lot in one day do not expect your house batteries to be 100% charged when you get to your destination.

rkurlan · 01-13-2017, 05:10 AM

Thanks very helpful

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Smitty3509 · 01-13-2017, 05:58 AM

Look at PJ's YouTube series, he covers all the most asked customer service questions. This is a great education video for all of us!

trimacon · 01-13-2017, 06:39 AM

Quote:

Originally Posted by rkurlan

Can anyone tell me if the alternator on the motorhome will charge the house Batteries when you're going down the road or do they just charge the coach Batteries

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For mine yes. Probably for you also.

brobox · 01-13-2017, 06:53 AM

Quote:

Originally Posted by 757driver

Yes, the alternator will charge the house batteries while driving but not as well as some think. When you start out driving for the day the alternator will charge the house batteries for 1 hour and then switch off. The net gain to the batteries for that 1 hour will be about 30-35 amps. The charge to the house batteries will remain off until the house batteries drop to 12.6v or less and then charge again for 1 hour. This cycle will continue for the driving day.

Unless you drive a lot in one day do not expect your house batteries to be 100% charged when you get to your destination.

Along with what Don is saying.......if you leave Walmart after running on battery power all night, run the generator for an hour or two while traveling in the morning. JMO, but over taxing the engine alternator is hard on it. The Onan is designed to charge large banks of batteries in a short period of time.

Unplanned Tourist · 01-13-2017, 07:07 AM

Quote:

Originally Posted by brobox

Along with what Don is saying.......if you leave Walmart after running on battery power all night, run the generator for an hour or two while traveling in the morning. JMO, but over taxing the engine alternator is hard on it. The Onan is designed to charge large banks of batteries in a short period of time.

Aren't the alternators in MH's designed to be able to charge at full capacity? Most alt's on the trucks are made to work at full load for extended time (ie. 160 amps at 14 volts continually) Just wondering.

I had a diode style battery isolator on the old Airstream, and it would put out full voltage to the house batts as long as the engine was running.

brobox · 01-13-2017, 07:36 AM

Quote:

Originally Posted by Unplanned

Aren't the alternators in MH's designed to be able to charge at full capacity? Most alt's on the trucks are made to work at full load for extended time (ie. 160 amps at 14 volts continually) Just wondering.

I had a diode style battery isolator on the old Airstream, and it would put out full voltage to the house batts as long as the engine was running.

Charging 2 truck batteries which the alternators are designed for, then adding eight 210 amp AGM batteries keeps a constant load on the alternator over and above their designed use. Why not just run the generator for an hour in the morning(if not already flyy charged) and let the alternator change the 2 truck batteries it was designed for? I am just one of those that like to use the systems as they were designed to be used and keep my batteries fully charged as much as possible....it helps them to last longer as well. See Don's post about fulling changing with the alternator. We have 12.5 kw generators and 170 amp alternators....which one will keep $3,000 worth of batteries in top condition? JMO

twinboat · 01-13-2017, 08:29 AM

Alternators will output 50% to 60% of there rating, all day and up to 75 % for the first 1/2 hour with no harm. MH chassis have large high output alternators for extra battery charging.

Even if you have a 15KW generator. It is only running a 50 to 100 amp battery charger. If it's an inverter/charger, it's a whole lot more expensive than an alternator.

Not all BIRDs have 1 hour timers in them, so charging keep going. Besides a discharged battery is less the 12.6 volts so it will restart quickly.

IMO, the MH builder went thru a lot of expense to install a good, logic based system, to not let it do its thing.