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Topic: 99' U270 Chassis Battery Question (Read 994 times) previous topic - next topic

99' U270 Chassis Battery Question

I was reading a FAQ from Barry Beam's website, and I learned for the first time, that the inverter (Freedom 20) doesn't charge the batteries when plugged into shore power. Currently I have the coach plugged into a 20amp circuit 24/7, but since I have seldom started the coach and let it run while I have been doing various repairs and renovations (currently the Bulkhead and subframe in the utility compartment), therefore the chassis batteries really haven't been being well maintained as the coach has been sitting. Reading the FAQ, I see that the Battery Boost switch can be left on and that will charge the chassis batteries from the house battery bank/inverter combo. I believe this happens as the generator is running or while plugged into shore power (or I suppose, just from the house battery bank itself).
My question is, how long/often should I have/leave the Battery Boost switch on to safely maintain the chassis batteries while the coach is sitting? The chassis batteries are optima red top, and the house battery is two MK AGM's.
Thanks,
Don
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: 99' U270 Chassis Battery Question

Reply #1 –
I left the boost switch on all the time I was plugged to shore power for many months. Recently I installed a Battery Tender to maintain the chassis batteries. It is on any time power from the inverter, shore connection, or generator are available. Now, I turn on the boost switch any time I start the engine, and turn it off the rest of the time.

The boost solenoid should be a continuous duty solenoid that could be left on all the time. Some folk recommend not leaving it on all the time. Alternatives for keeping the chassis batteries charged while parked include Trik-L-Start, Battery Tender, shore powered relays, and "home brew" switches or diodes. A search of the forum should yield several discussions.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: 99' U270 Chassis Battery Question

Reply #2 –
J. D., thanks for sharing what your practices have been regarding the boost switch. I guess I will leave it on for a day or two and let the chassis batteries get some love while I figure out a long term approach... just another example of something for me to get up to speed on with these coaches!

Anybody offhand know where the battery boost solinoid is located in the coach? I figure I should have a look at it and make sure the connections are secure and that it doesn't get too hot.
Don

Quote from: J. D. Stevens –
I left the boost switch on all the time I was plugged to shore power for many months. Recently I installed a Battery Tender to maintain the chassis batteries. It is on any time power from the inverter, shore connection, or generator are available. Now, I turn on the boost switch any time I start the engine, and turn it off the rest of the time.

The boost solenoid should be a continuous duty solenoid that could be left on all the time. Some folk recommend not leaving it on all the time. Alternatives for keeping the chassis batteries charged while parked include Trik-L-Start, Battery Tender, shore powered relays, and "home brew" switches or diodes. A search of the forum should yield several discussions.
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: 99' U270 Chassis Battery Question

Reply #3 –
The boost solenoid should be located in the proximity of the battery isolator.  Mine is located behind the duallies on the driver's side (street side in RV lingo).
 
I had posted before that you should take a baseline voltage reading of all batteries plugged and not plugged; genset running and not running, boost solenoid on and off just so you know how everything works.  You'll be the wiser for it.  Good luck!
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: 99' U270 Chassis Battery Question

Reply #4 –
Don, I also have a 99 U270. My solenoid is under the bed next to the isolator. If you leave the boost solenoid on make sure you are charging the same type of batteries as the house.

Regards, Mark
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Mark and Tanya
Milton , Florida
US Navy Veteran (DV)
1999 U270 Special 40' CAI , 2015 Jeep Wrangler Sahara

Re: 99' U270 Chassis Battery Question

Reply #5 –
Thanks Mark,

I believe the Optima redtop batteries are AGM like the house batteries (MK 8D), so that should be fine...
Don
Quote from: Mark Zettek –
Don, I also have a 99 U270. My solenoid is under the bed next to the isolator. If you leave the boost solenoid on make sure you are charging the same type of batteries as the house.

Regards, Mark
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: 99' U270 Chassis Battery Question

Reply #6 –
Thanks Pete,
Added to my list of projects! At least this one is finite...
Don

Quote from: Peter & Beth –
The boost solenoid should be located in the proximity of the battery isolator.  Mine is located behind the duallies on the driver's side (street side in RV lingo).
 
I had posted before that you should take a baseline voltage reading of all batteries plugged and not plugged; genset running and not running, boost solenoid on and off just so you know how everything works.  You'll be the wiser for it.  Good luck!
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: 99' U270 Chassis Battery Question

Reply #7 –
The boost solenoid is on the front wall under the bed.  Turning the boost on one day a month should do find keeping the chassis batteries up.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R
 

Re: 99' U270 Chassis Battery Question

Reply #8 –
James Triana said not to leave it on all the time, rather put it on one day a week for 24 hours at one Grandvention I went to.  He did a whole seminar on batteries and chargers and alternators two years running.
 
I put Trickle charge on and it keeps the start batteries topped off.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon