Battery not holding a charge

[The Hawk-JAY]

Seems that after taking full charge it takes only a night for the battery to be down to 1/3. Battery is one year old and came with the Greyhawk. Battery is full of water and all the connections area tight and clean. Is this just bad battery?
The Hawk

 

[SecretCoveDave-JAY]

Does there appear to be material adhered to the plates in the battery?

Hey Hawk, hello and welcome to the group.
Dave

 

[Quahog]

Seems that after taking full charge it takes only a night for the battery to be down to 1/3. Battery is one year old and came with the Greyhawk. Battery is full of water and all the connections area tight and clean. Is this just bad battery?
The Hawk

Jim, pick up a hydrometer and measure the battery. They're cheap... it will give you an accurate reading on whether or not the battery is good or needs replacing.

 

[The Hawk-JAY]

Nothing on the plates and off the the auto parts store to buy a cheap hydrometer.
The Hawk

 

[drfife]

Nothing on the plates and off the the auto parts store to buy a cheap hydrometer.
The Hawk

Buy a new battery while you are there....

 

[Terry-JAY]

Hard to tell without knowing how much you are pulling - that could be correct if you pull too much or something is draining it. If you are in the market for a multimeter, get a good AC/DC clamp meter -- they are great for this sort of thing. The DC ones are harder to find, so look close. Got mine at Sears...it was a pretty good model for about $50.

 

[norty1]

Most auto parts stores have a battery tester that can tell you in 3 minutes if the battery is bad.

Take it with you.

 

[Grumpy]

If you bought it new remember you have a 2 year warranty on everything.

 

[cdrcos@gmail.com]

If you bought it new remember you have a 2 year warranty on everything.

Actually, most batteries are warranted for much longer than that...

 

[Chakara]

I know this is a Class C forum, but this applies across models. My trailer (see below) had 6 guage wire run from the battery, all the way to the back for the power distribution panel - probably 20-30' of pretty narrow guage wire.

A few things about batteries - for a float charge you need to be getting 13.4 V @ the terminals....that should give you about a 1AH charge rate (VERY SLOW). So, lets say my factory 2 stage converter is doing a good job and putting out 13.6V for trickle charge. The issue now is cable loss.

I used http://www.nooutage.com/vdrop.htm to calcualte how much voltage drop I get across that long cable run. Assuming 25' of 6awg and only 1 amps of draw, I don't do well with .2% voltage drop. That sounds like a small number, but it means I'm only putting 11V on my batteries. IE: My batteries had NEVER had a good charge off the converter.

Even if my converter was putting out a much better 14V, at .1% drop over that cable I'm only getting 12.6V at the terminals - IE: getting what a fully charged battery has - and as I'm not putting more voltage on it than the battery has itself, I am getting no charge!

No matter how much I ran the generator, I could not make it through more than a night with no heater!!

My fix was replacing the 2 stage with a good 3 stage converter, and relocating the converted to the front of the trailer. I ran larger gauge wire back to the power distribution panel and a nice 4G wire the ~5 feet from the new install location to the batteries. I also replaced the now shot 2xGroup 24's with 2xGolf Carts. I'll try to get around to doing a proper write up on this mod as I suspect MANY more people out there need to consider doing something similar.

It wasn't a simple job - and a fair understanding of cabling/wiring is recommended. However, now I can boondock with confidence.

To really see how your batteries are doing, get an inexpensive 12V meter and a hydrometer. Should be out less than $30 for both and be able to KNOW where you sit.

This is a long read - but very good info and where I started. 12V Side of Life Then when I got serious about the mod, I got involved over at the Wind Sun Forums. Those wind-sun guys are solar, but the concepts are the same and that is where I learned the most.

-Good luck!

-Chak

 

[Quahog]

Excellent post, Chak. I'm getting ready to replace my Grp 24 12V with two GC2's (6V) that I picked up today at Sams Club. On Roy B's advice, I picked up a 25' spool of 4AWG wire, lugs, grommets, bus bar, fuse, etc. Over the next week or so, I hope to complete this mod installing the two new batteries in a front mounted toolbox.

Thankfully, my converter has "Charge Wizard" technology built-in. I want to do this incrementally (as I can afford to) but eventually, I will add a 1500-2000W pure sine wave inverter to the mix. Maybe someday, solar panels....

 

[Riplin]

We have a 31 FS. If we use the furnace at all the battery is always at 1/3 in the morning. I changed the battery and it is still at 1/3 in the morning. IMHO just not enough battery for the motorhome, Jayco should of made room for a second battery.

 

[Chakara]

We have a 31 FS. If we use the furnace at all the battery is always at 1/3 in the morning. I changed the battery and it is still at 1/3 in the morning. IMHO just not enough battery for the motorhome, Jayco should of made room for a second battery.

Riplin - keep in mind that the meter built into the camper is not accurate by any means. It can come close, but will never be a good indication. Most importantly, when you check the battery, make sure ALL loads are turned off. Preferably, leave them off for an hour or two (but I realize this isn't practical when camping).

Those built in meters are especially bad for telling when the battery is full. Are you camping, running a generator for a few hours to charge (checking the meter as to when to quit charging?) Sadly, this won't work out well as you get higher readings than reality right after/during charging.

Check your battery, with a cheap volt meter and hydrometer. This will give you an idea if it may just be bad.

31 foot is a big space to heat - it may take quite a battery bank to do better. That said, optimizing what you have may help. How far is your converter from the batteries? I ask because many models have WAY to much wire between the 2. This prevents the batteries from taking a charge without 10's of hours of generator time.

Also, look at your converter. If you are re-charging with a generator, a 2 stage converter will take 10+ hours, whereas a 3 stage can get you to 90% in a couple of hours. (lots of variables here, but in general)

Hope this helps...

-Chak

 

[Riplin]

Riplin - keep in mind that the meter built into the camper is not accurate by any means. It can come close, but will never be a good indication. Most importantly, when you check the battery, make sure ALL loads are turned off. Preferably, leave them off for an hour or two (but I realize this isn't practical when camping).

Those built in meters are especially bad for telling when the battery is full. Are you camping, running a generator for a few hours to charge (checking the meter as to when to quit charging?) Sadly, this won't work out well as you get higher readings than reality right after/during charging.

Check your battery, with a cheap volt meter and hydrometer. This will give you an idea if it may just be bad.

31 foot is a big space to heat - it may take quite a battery bank to do better. That said, optimizing what you have may help. How far is your converter from the batteries? I ask because many models have WAY to much wire between the 2. This prevents the batteries from taking a charge without 10's of hours of generator time.

Also, look at your converter. If you are re-charging with a generator, a 2 stage converter will take 10+ hours, whereas a 3 stage can get you to 90% in a couple of hours. (lots of variables here, but in general)

Hope this helps...

-Chak

Thanks for the input. We dry camp about 50% of the time. I checked the battery voltage at the battery with the gen running and found it to be 13.2volts. Way too low to put a real charge into the battery. With that being said we can drive all day and spend a night with the furnace on still have the battery at 1/3 or below. I know the gauge in the command centre is cheap, not the greatest. But when there isnt enough battery to start the gen it is 1/3 or alot lower. I bought an external battery charger and 2 2000w champion inverter gens as well as a second battery to hook up when we camp in cold weather. The single battery is along way from the converter. But I have no desire to change that. I will add a permanent 2nd battery this summer in an outside storage compartment. I still believe that Jayco did a disservice by only providing one battery compartment on such a large RV.

 

[The Hawk-JAY]

Well took the greyhawk back to the dealer to find out what was draining the battery over night. The tech found that a solenoid was not closing and was causing the draining. Battery checked out OK.
The Hawk