Fried battery

[JOERVDREAM]

I started to smell this rotten egg smell and after a lot of crawling around I traced it to the chassis battery. It was really hot and giving off that terrible smell. I disconnected it and took it out side and it took about 3 hours to cool off. I put a new one in the next day. I talked to someone later that told me to keep the aux battery switch off while Im connected to shore power because it over charged the battery? Or was there some other reason this happened and why only the chassis battery? The book says always keep the switch on unless your going to be hooked up to shore power for a long time while in storage. I have had the switch off since I put the new battery in for about a week now. Any ideas?

[JOERVDREAM]

Thanks for all the input. I have a new to me 05 Winnebago sightseer 29R. The battery was a maintenance free battery. Low miles but things have timed out and I imagine long periods of being idle. I will be changing out the coach batteries next. The generator only had 30 hours but Im going to get it serviced as well. Last week was kinda crazy seems like everything I touched broke. But I wouldn't change a thing Im really all around happy with my new world.

[Sam_Spade]

Gjac wrote:
How did a bad battery cause all those problems?

It didn't.
The battery going bad was a SYMPTOM and not the cause.

[Gjac]

down home wrote:
Last year battery in our Factory Edge failed.
Wife was driving down the road and smelled what you smelled. Pulled over cut the engine off opened the hood but didn't know what was wrong. Found a small reapir shop down the hill. He saw the battery was hot and boiling and about to explode.
Replaced it with a NAPA which would not hold enough charge to start the car first of this month,result in cascading visiting Ford Dealers in Russelville Ark, Shawnee Oklahoma, and Camping World, in Oklahoma City, and For Dealer in Texas.
New Battery, radiator fan, rewiring the car at CW, and water pump in Texas.
Take too long for all the details but about $4,000.00 from a bad new battery!

How did a bad battery cause all those problems?

[azdryheat]

We cook several batteries at our RV shows. The water levels get low and the charging cooks out the rest of the water. I've documented that my own trailer did that a few weeks ago, lack of water.

[wa8yxm]

I see a lot of "Old RVers Tails" here in the forums

The bit about keeping the AUX switch OFF when plugged in due to over charging....

Well long long time ago.. There were some very bad converter/chargers one of which was the Magnatek 6300.. These used big heavy feroresnate transformers (you need not know what that means) and were designed for 110 or 115 volts. Well the standard voltage has gone up since I was in school from 110 to 120 so this means the 6300 ran "Hot" (overcharged) also though the charger was only a few amps (The converter usually was around 30 amps but the charger less than 5) it had no clue as to when to stop.. So it overcharged.

Have not made any of those in years. The company was bought out and the new owners scrapped that line they make a much better one with decent regulation and a switching converter Smaller. Cleaner, Lighter and more efficient.

[midnightsadie]

theres more to this story? when did you check the water level in the battery? most likely theres nothing wrong if you didn,t do some maintance on your unit.but you should check the charging system to make sure.

[Chum_lee]

"I talked to someone that told me to keep the aux battery switch off while I'm connected to shore power because it over charged the battery?

You don't provide any information about your MH. The "aux. battery switches" I've seen are the intermittent contact type meaning that the chassis battery will only be manually interconnected to the coach battery(s) while you press the (usually a rocker type) switch. Yours may be different, but you need to be clear on what type of switch you have. Most batteries (coach to chassis) are automatically interconnected by a solenoid whenever the chassis engine is running but NOT when connected to shore power. (engine off)

Chum lee

[CA_Traveler]

I'd check the charger to make sure it's charging the new battery correctly.

[Sam_Spade]

It takes a LOT of current to make that happen.
The most common cause is shorted contacts on the starter solenoid, keeping the starter running (or trying to) a lot longer than it should.
The second most likely cause is a short inside the battery itself.

The charging equipment in an RV is generally not capable of pumping in that much current, unless it has had a massive failure internally.

EVERY RV OWNER NEEDS A VOLTMETER.

Then.....turn that switch back on and see what happens.
AFTER you get a voltmeter so you can monitor what is happening.

IF your chassis battery was cooked by the charging equipment in the "house", then your house batteries should be toast too.

[down_home]

Last year battery in our Factory Edge failed.
Wife was driving down the road and smelled what you smelled. Pulled over cut the engine off opened the hood but didn't know what was wrong. Found a small reapir shop down the hill. He saw the battery was hot and boiling and about to explode.
Replaced it with a NAPA which would not hold enough charge to start the car first of this month,result in cascading visiting Ford Dealers in Russelville Ark, Shawnee Oklahoma, and Camping World, in Oklahoma City, and For Dealer in Texas.
New Battery, radiator fan, rewiring the car at CW, and water pump in Texas.
Take too long for all the details but about $4,000.00 from a bad new battery!

[Artum_Snowbird]

Normally, as your battery charges, it develops resistance to charging and the charging current drops to zero.

When you have a battery that has a cell that has collapsed inside, the current in that cell merrily runs along, but it sees the battery as not charged, so it throws the maximum charging current through the battery trying to charge it.

The result of this current flow is an off gassing, and cooking of the battery.

What I did was I got a very cheap ($3.00) (Banggood) two decimal point voltage meter and put it across the battery terminals. Now, I just need to look at the meter to determine my battery voltage. I can monitor the amount of usage over time by checking the voltage. I can also monitor the drop in voltage when I hook up a big load like the furnace motor.

Keeping an eye on your battery and understanding what is normal, and what is not becomes a habit, and after a while you just glance at the voltage and know everything is OK, or something is wrong.

[Executive45]

Batteries fail. Generally 5 yrs is max but some 6VDC last longer. Anyway, my guess is your battery failed internally and cooked itself. Follow your manual's advice. Check your batteries monthly to ensure water levels are up. Also, if you have a battery bank, one weak battery will drag the others with it....Dennis