chassis batteries

[rex unicume]

Is there any special way to charge these batteries with a portable charger?
Which terminals do you attach the charger terminals to?
It has been sitting quite a few months and the chassis batteries are dead.

Are there any ideas about keeping the chassis batteries charged other than running the unit?

[Joel Ashley]

First of all, it would help to know which model and year of coach you have.  Several different built-in charging options are possible depending on that information.  I'm no expert on them all, but others here will be more able to help if you supply more info.

Generally you need to turn off both chassis and house master switches upon storage of the rig, but on most units there will still be some parasitic drain.  If the coach is outside exposed to sun and has a solar system, that can help keep the batteries up during storage.  Otherwise, it may be best to disconnect the batteries altogether.

If the coach is plugged into electricity during storage, an onboard charger that works properly should keep things up.  They can be part of the inverter or some rigs use what's called Echo Chargers.  But sometimes those chargers fail.  As mentioned, a lot depends on which coach we are talking about.

Chassis batteries aren't designed for deep discharge like house batteries are.  Once they take a hit like that, they are never quite the same again.  Nevertheless, you may be able to resuscitate them by hooking the red lead of a portable charger to the positive post of one and the black lead to the negative post of the other, but it will take awhile.  Some coaches' generators start off the house batteries;  if they are still up, and they may very easily be shot too, you might be able to start the genset and use it to recharge the chassis bats, but that is not the most likely of plans.

Joel

[rex unicume]

thank you.
It is 1997 Patriot with 300 cat.
It has been plugged in most of the time.
The house batteries are fully charged according to the guages, but not the chassis.
I thought being plugged in would charge both sets of batteries.
Big learning curve.
Thanks
Rex

[Joel Ashley]

I'm out of my element when it comes to Echo Chargers, but I'd hazard a guess that it is what you have on board.  If it charged the house but then didn't switch over and charge the chassis, the automatic switchover part of the Echo Charger may be faulty, as per common threads here on the Forum.  Or you may simply need new chassis bats.  But I'll leave that analysis to others here that are more astute in that regard.

Be patient;  someone will chime in with more information you'll find useful.  In the meantime, here's hoping you can get charged up and going again.

Joel

[rex unicume]

Thanks Joel
Much appreciate the input.
Cheers
Rex

[Bill Dean]

I had the same problem with our 2001 Beaver Patriot Tic 37.  What I did was to install marine grade rotary switches for both banks of batteries on each side of the battery bay.  As we store our rig in a covered storage, the solar charger was all but useless thus the drain.  
The genset starts off of my chassis batteries so I jump started the genset from the Jeep through the chassis batteries and then, using a toothpick, held the battery booster on for two hours while all house and chassis batteries fully charged.  That's when I then installed the rotary switches and all has been perfect since.

[rex unicume]

I gather this rotary switch shuts off the batteries so there is no drain.
Great idea.
Cheers
Rex

[Joel Ashley]

Yes, Bill brings to mind that not all coaches came with master switches, and all should have them.  The marine grade ones are best.  Below note the factory red rotary switches on the panel above my battery set.

Joel

[rex unicume]

Thanks so much.
Will investigate getting this done.
Rex

[Keith Oliver]

Rex:

When I bought my Contessa, it came with low chassis batteries.  I was unable to be plugged in every night over the first week of ownership (traveling and waiting to get across the border) so the chassis batteries failed completely and I replaced them.  Then I had to leave the coach unplugged for another 3 weeks, and the chassis batteries were totally discharged again.  Talk about a steep learning curve.  I got going, then determined that the charging of the start batteries, from shore power, was not happening at all, and there was a continuous draw from the CAT ECM of about 2 amps.  SO now I know why the batteries were discharged, and why they were staying that way.  I put a small charger on them, dedicated to just the Chassis batteries, but it failed within a year.  I then put a relay type isolator/charger (sometimes called a BIRD system) that takes power from the house batteries when they have enough of a charge and charges the chassis batteries.  Since doing that, no further problems with charging.  I also put a positive shut off, a knife switch, on the negative terminal of the chassis batteries, so that when there is no charging power, there can also be no load whatsoever.  Again, no further problems.

[Gerald Farris]

Rex,
Some of the 97 Patriots have an Echo Charger, but not all. The first thing that you need to determine is if your coach has an Echo Charger or not. If not, you should install something to charge your chassis batteries when the house batteries are being charged. If you have an Echo Charger, then you need to determine why it is not charging the chassis batteries. The most common reason for an Echo Charger not working is a bad fuse. There is a 20 amp fuse in each of the wires to the Echo Charger, and you will need to check both.

If you do not have an Echo Charger, you have to options to cure the chassis battery charging issue. The easiest and cheapest method is to just install an Echo Charger, preferable the Magnum brand unit. However, the best option is a marine grade "Bird" system. This type system is a little more money, and a little bit more involved to install, but it works great.

Gerald