Batteries

[rwilson]

I have mistakenly left power on and upon return both coach and house batteries have totally run down so I am unable to start the engine. Is there a way to leave the engine batteries alone so I can always start?

 

[Beau388]

I have mistakenly left power on and upon return both coach and house batteries have totally run down so I am unable to start the engine. Is there a way to leave the engine batteries alone so I can always start?

It would help to know the year and model of your coach. That said, most coaches have the chassis and house batteries separate. The batteries are only connected by the emergency start switch and or when charging. To discharge the chassis battery on a plant 750 coach you would have to leave items on in the front cap (map light, fans, mirror heat,etc). Discharging the house batteries would not normally effect the chassis battery. Both sets of batteries can be equipped with a manual battery disconnect.

 

[rwilson]

It’s a 2019 Thor Hurricane 34R. Nothing was left on other than power switch, I guess inverter too so I suspect refrig ran it down

 

[Beau388]

It’s a 2019 Thor Hurricane 34R. Nothing was left on other than power switch, I guess inverter too so I suspect refrig ran it down

The inverter powering the frig will run the house batteries down (assuming two 100 amp-hr flooded batteries - 50% remain capacity) in about 18 hours. Flooded batteries loose capacity every year at a rate of 6% or so. None of this explains why the the chassis battery under the hood did not retain a charge. Typically a flooded chassis battery will go flat in about 4 weeks due to the draw the keep "alive circuits" in the engines computer and the cab radio. If you are going to store the coach for a month or more, it is recommended you install a manual battery cut-off switch. Basically, the coach's engine is meant to be exercised at least once a month along with the generator. The ideal situation is to leave the coach plugged into to a 15 amp or greater circuit. I am fortunate to have an assigned parking spot with a 50 amp pedestal, but the chassis battery and one house failed 3 years. Just to be safe, I replaced all three last year.

 

[lwmcguire]

Beau388 laid it our pretty well

The two batteries systems shouldn't have been connected as one or the other discharged so you have two things going on

I always disconnect the chassis batteries when storing but did have a disconnect switch already designed in. I added a disconnect for the Chassis battery bank for longer term storage.

 

[Bob Denman]

To get things started: put some jumpers to the coach batteries, and get your generator started. That should charge the coach batteries (if the switch for the batteries has them connected)
Once they're taking a good charge: jump the chassis battery, and start the chassis engine.

 

[lwmcguire]

To get things started: put some jumpers to the coach batteries, and get your generator started. That should charge the coach batteries (if the switch for the batteries has them connected)
Once they're taking a good charge: jump the chassis battery, and start the chassis engine.

Bob is right, and let the batteries charge up for 15 minutes or so before trying to start anything

 

[EA37TS]

Actually, when the house batteries are charged use the emergency start switch to start the engine.

 

[Bob Denman]

That'll work...
But since the jumper cables are already out

 

[EA37TS]

That'll work...
But since the jumper cables are already out

Class A chassis batteries aren’t always easy to get to with cables.

 

[Bob Denman]

How about a 1000 amp jump-starter powerpack?
I've got one from Rugged Geek, and it rocks the house!

 

[Paul0138]

I would get a battery charger and charge the batteries with that. Charging a dead battery with the alternator is not a good idea. Also, would recommend getting a battery tester to make sure the batteries are still good, one with a load test.

 

[macdaddy1111]

It’s a 2019 Thor Hurricane 34R. Nothing was left on other than power switch, I guess inverter too so I suspect refrig ran it down

And that is why I have couple panels! Last thor without panels, I would forget to turn everything off and puff, I be dead! ha!

 

[howzball-THOR]

And that is why I have couple panels! Last thor without panels, I would forget to turn everything off and puff, I be dead! ha!

Same here. I don't have enough panels to do much but they do keep the batteries charged when it's parked.

Since switching the coach batteries to lithium I don't have to worry as much about the phantom loss like lead acids but the panels are still nice for the truck batteries.

 

[SuperBoar]

Emergency start switch

Everybody has different systems, but on my 2017 Vegas 24.1, the emergency start switch must be held down for several minutes so the coach batteries can quick charge the chassis battery. You'd think it was just a relay to "shunt" all the batteries together, but my dealer says otherwise. If your chassis battery is close to three years old and you don't run your engine every month or so, it will go bad and you just have to jump it off which is way tedious because the battery is so inaccessible, then install a new battery.
There has been a lot of discussion about how the systems that charge the house batteries also charge the chassis battery. Not true for my rig. Plugging into shore power does not keep the chassis battery topped off - again, that's the way mine is wired. Some keep trickle chargers on the chassis battery.

 

[exit55]

Class A chassis batteries aren’t always easy to get to with cables.

I find the positive terminal is not too hard to get to. the neg one is a b----. I took a wire like you use to connect batteries together (ie golf cart). Removed one of the frame bolts near the battery, twisted it together so both ends go under the frame bolt. skinned the wire in the middle. This serves as my ground (negative ) terminal.

 

[howzball-THOR]

There has been a lot of discussion about how the systems that charge the house batteries also charge the chassis battery. Not true for my rig. Plugging into shore power does not keep the chassis battery topped off - again, that's the way mine is wired. Some keep trickle chargers on the chassis battery.

Is that true of all of the Vegas models? I would have assumed they were like any other class A coach and anytime you're plugged into shore power the system keeps all of the batteries charged unless maybe you're turning off a disconnect switch?
The (BiRD) relay connects to the button that helps you jump start your truck batteries, it should also keep both sets of batteries charged while on shore power.

When my BiRD switch's trombetta relay failed it caused my truck batteries to not charge, it was stuck only charging the coach side batteries.

Someone who owns a Vegas model probably know more about it but, I think your truck battery is supposed to charge on shore power.

 

[Hugh.vines@att.net]

Is that true of all of the Vegas models? I would have assumed they were like any other class A coach and anytime you're plugged into shore power the system keeps all of the batteries charged unless maybe you're turning off a disconnect switch?

The (BiRD) relay connects to the button that helps you jump start your truck batteries, it should also keep both sets of batteries charged while on shore power.



When my BiRD switch's trombetta relay failed it caused my truck batteries to not charge, it was stuck only charging the coach side batteries.



Someone who owns a Vegas model probably know more about it but, I think your truck battery is supposed to charge on shore power.

Yes mine is like that 2016 axis

 

[Beau388]

Everybody has different systems, but on my 2017 Vegas 24.1, the emergency start switch must be held down for several minutes so the coach batteries can quick charge the chassis battery.

True The emergency start switch simply uses the house battery charging system (coach's alternator and chassis) to connect the connect the house and chassis batteries even if the engine is not running. So if the house batteries are low and the generator cranks slow, using the emergency start usually will supply enough current to start the generator. The converse is also true. The reason to hold the switch down is the capacity of the Trombetta relay or the BIC. The Trombetta can handle about 100 amps and the BIC about 60 amps continuous. The generator's starter need s 60 amps and the V-10's starter needs 400 amps, so it takes a while to move those amps from one place to another. Good jumper cables will move about 400 amps.

 

[16ACE27]

There has been a lot of discussion about how the systems that charge the house batteries also charge the chassis battery. Not true for my rig. Plugging into shore power does not keep the chassis battery topped off - again, that's the way mine is wired. Some keep trickle chargers on the chassis battery.

Then you have a problem with your coach. All Axis/Vegas models have BIRDS/BIMS to connect the two battery systems when charging and disconnect them when not. It is not uncommon to find that they were wired incorrectly from the factory.