Battery Drain

[beef56]

Our Reflection has been parked and not in use for about a month. The 110 was not connected and Sunday I checked and the battery was dead. I plugged in the 110. Last night the indicator show battery full so I unplugged the 110. Tonight the battery had discharged 25%. I cant find anything that is turned on. I didn't have the battery disconnected. I have never had this problem before on any other RV's. Obviously there is something draining the battery. I can disconnect the battery but does anyone have an idea what might be draining it?

 

[Retread68]

beef56 - there are several 12-volt lines that will remain hot when shore power is cut, although only one should be pulling constant power from the battery that I can think of right away, that being the CO/LP detector/alarm. It is straight wired to the battery on mine. If your battery has discharged 25% in 24-hrs with nothing on, after a full charge then you may have a damaged cell. You might check to be sure all cells have water and check it with a good ohm/multi meter.

 

[Bigpops]

I believe the converter is always drawing power also. Only way to slow the draining is rouse the battery disconnect switch.

 

[J&G garage]

My owner's manual says to disconnect the battery during storage as the battery disconnect switch doesn't kill all the circuits. Draining a battery completely can be fatal to the battery. Maybe find a battery retailer that can do an equalization charge for you which can remove sulfation from the plates and restore some battery capacity. Good luck.

 

[JCR GD]

Our Reflection has been parked and not in use for about a month. The 110 was not connected and Sunday I checked and the battery was dead. I plugged in the 110. Last night the indicator show battery full so I unplugged the 110. Tonight the battery had discharged 25%. I cant find anything that is turned on. I didn't have the battery disconnected. I have never had this problem before on any other RV's. Obviously there is something draining the battery. I can disconnect the battery but does anyone have an idea what might be draining it?

If I read this correctly, you checked battery level while plugged in? If so, my battery levels always show full when plugged in (they are being charged) so I unplug for true battery level.

I'm thinking you didn't get a full charge.

 

[J&G garage]

Also keep in mind that for an accurate indication of state of charge the battery must sit for 24 hours with neither a charge nor a drain on it. Otherwise it may show more capacity than you actually have. I don't know the output of the chargers on our Grand Designs but for a reasonable recharge time the charger should have an output of at least 25% of usable battery capacity.

Jim

 

[Jannnan]

Don't know what kind of battery you have but mine came with an Interstate and it's a piece of junk, I'll be changing it to an Excide from Camping World real soon.

 

[Steve and Lynne]

Coming from an auto repair shop where we sold Interstates almost exclusively, I have noted that their failure rate has increased somewhat in the last few years. However they have many, many vendors across the country, both service operations and stand-alone stores, so warranty replacement is readily available wherever you are, similar to Exide. Interstate has a simple and generous pro-rating policy for their warranty adjustments. We put two Interstates in our Ram diesel last January, and I had to replace one in the Dallas area in March. We also had to get our Interstate replaced in our Reflection in April at N/C. Both Exide and Interstate do not build their own batteries, very few manufacturers left.

 

[offtohavasu]

I two have noticed a decline in Interstate quality on my truck. With two batteries it really sucks, because the bad battery will kill the good one. That being said, Interstate/Interstate dealers have stood behind the battery and I have had zero issues getting a replacement. So for now, I'll stick with them given their track record of standing behind the product. I've seen many different brands of batteries failing quickly, so this is not limited to an Interstate issue.

 

[beef56]

I had it unplugged from 110 when the battery indicator was 100%. It was plugged in for several days before I unplugged and checked it. I doubt the battery indicator in the RV is 100% accurate either. I know I can use the battery disconnect but I don't feel it should be necessary for only 24 hours. I will load test the battery and yes it is an Interstate battery.

 

[Cate&Rob]

The simplest way to discover if the problem is within the battery or with loads that you are not aware of, is to fully charge the battery and then disconnect the negative terminal for a few days. When you reconnect, at least you will know which to investigate further.

Rob

 

[offtohavasu]

To get a good result, do as Rob mentioned, but before hooking it back up, use a digital multimeter and see what the volts are. Measure after you charge and then measure again a day or two later. You should not see a drop, or very little. If more than that, bad battery. IF it drops when you hook it up, you have something pulling a load.

 

[JustinThyme]

Load test isn't 100% reliable. Battery current is a chemical reaction and may load test fine after a complete charge then drain or even fail the next day. The only reliable test is internal impedance but those testers are expensive. IEEE standard dictate 72 hours of uninterrupted charge cycle with no drain at all before testing. If you are anywhere near me I have an impedance tester and would be more than happy to test it for you.

The nature of RVs and how they are wired will have the converter drawing some current from the battery. Also your fridge controls will always be pulling a little. The only way to reduce possible loads is to pull the disconnect, this is most of the reason they are installed and are in an easy to access location. Others install a disconnect the removes everything from the circuit and connect directly to the battery. I have seen some mention using the negative to disconnect but I highly discourage this as its grounded negative system. Any loads downstream will then put a positive charge on the entire frame and will offer no protection on short circuits.

 

[Cate&Rob]

Hi Rob (@JustinThyme)

I usually agree with your advice, but can't agree with disconnecting a positive battery terminal first. Disconnecting either terminal isolates the battery potential from any loads. Disconnecting the negative terminal first is standard practice In the automotive industry. This is primarily a safety issue, to keep the wrench at the same potential as all the surrounding metal. Imagine what happens when the wrench gets jammed between the positive terminal and a fender brace, if the negative terminal is still connected ! Jamming the wrench between the negative terminal and that fender brace, is no big deal, even if the positive is still connected.

(another) Rob

 

[offtohavasu]

I don't want to speak for the other other Rob, but I don't think he's saying physically disconnect the positive post, but mechanically disconnecting the positive post.

 

[JustinThyme]

I was referring to installing a disconnecting means on the positve terminal like a switch or relay. I agree 100% to disconnect negative first when physically removing the battery.

 

[Cate&Rob]

Keep in mind that the OP is asking how to determine whether something is draining his battery or does he have a bad battery ? Not how to rewire his coach to install a true battery isolation switch (which BTW, I agree should be on the positive side). The safest and simplest way for him to do this is to disconnect the negative terminal for a few days and see what happens. A DC inductive digital ammeter could also answer this question, but I suspect he doesn't have one of these .

Rob

 

[JustinThyme]

The only way to truly find what's pulling current would be a DC current clamp. I've seen batteries that will hold a charge with no load at all yet deplete faster than they should with a small insignificant load. I think we all agree that running a battery completely dead is not synonymous with longevity of the battery and that even with the factory disconnect pulled there are devices that are still connected.

If it's any help I will put a DC current clamp on mine when I'm down there this weekend and let everyone know what the current draw is with everything off and the factory disconnect left connected. It should establish a reasonable baseline that should apply to most. It's on my to do list anyhow to do an actual electrical analysis of the entire coach so I know what actual loads are instead of relying on a very broad and possibly inaccurate chart. I'll be more than happy to assist anyone in my area with diagnostics as I do have a full compliment of calibrated test equipment.

(The other Rob) lol

 

[Cate&Rob]

As another reference point, we stored our Reflection 303 for six weeks with the OEM disconnect off, but battery connected.
We have the Group 24 Interstate battery installed by the dealer. (I know . . . it should be a Group 27 per the owners manual . . . but it is what it is). Came back to find that the landing gear worked without a problem.

Reference point #2 . . . I store my boat for seven months (it's Canada, eh,) with all six of its Group 27 ($100 each at Walmart) batteries disconnected. These batteries are at 80% when I come back in the Spring.

Rob

 

[Canyonlight]

Rob and Rob -- you guys are really sharp engineers sharing outstanding technical expertise (much appreciated) but I got a feeling you could do a smokin standup !!! We will be taking our rv out of storage on Monday and as noted in an earlier post in this thread I will share my findings re: our batt condition after nearly 7 months of sd winter/spring.

Just Dan