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kportra

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Montana
I'm starting to think we have a short.  Our new 2017 Heartland Prowler Lynx 18LX has some electrical issues - using too much.  This is a little trailer and we are outside most of the time not using electricity.  It's just my husband and I.  He does have a CPAP that he uses on 12 Volt every night.  We have 2 group 24 batteries (total of about 180 amps).  The CPAP is rated at 5 amps and he doesn't use the humidifier when we are camping.

So most days in the morning we wake up to flickering lights.  I know families that camp with the same batteries, more people, 2 CPAPs and they can go two nights before they have to run their generators to recharge the batteries.

So my question is:  How do we troubleshoot this?  The dealer does not seem interested at all in looking at it (they never call me back).  I'm thinking it would be pretty easy when stapling up the panels at the factory it would be pretty easy to nick a wire.  We would love to solve this before next summer.

Thanks in advance.
 
your batteries are closer to 150 amp hours at the C/20 rate and you can only use about 34-40 before they start aging very fast.. 5 Mpas times 8 hours your batteries are DEAD when you wake up

A pair of GC-2 Golf car batteries should fit in the same tray. They are however TALLER.. The pair, wired in series gives around 220 amp hours (210-250 depending on specific  sub model, mine are 230) YOu can safely use HALF that's over 100 amp hours. nearly 3 times the power you have now, before fast aging sets in.

NOTE they do take longer to recharge too.
 
No matter what batteries you're using, they need to be fully charged between discharges.

https://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/

 
I know that we could do bigger/better batteries.  I'm looking into some solar to assist in the recharging.  However - I do still feel there is an issue since we have friends that run two machines (same ratings) at night and don't deplete their batteries in one night.  Before I go spending a bunch on batteries, solar, etc. I want to troubleshoot the system.  I've also noticed that just sitting in the yard between trips, the batteries are low within a week with no load.

How do I tell if there is a short?
If I am able to determine this, then how do I tell which circuit is shorted?
 
The point I was trying to make is even though you don't have solar, whatever you are using to charge the batteries needs to be capable of delivering a full charge.
 
If you are convinced that something is wrong, and you are using too much battery with nothing on, then you must shut off everything, disconnect the batteries, negative lead only, then hook up a meter from the negative lead back to the battery set to read amps. Most any VOM will read up to 10 Amps, so get one and hook it up to read amps between the negative lead and the battery. This will tell you how much current you are actually using, I would expect 20 to 30 milliamps with nothing on, any more than that I would start looking for a problem. Keep in mind there are a few things that stay on and use 12V power even when everything is turned off. Chief among them are the LP/CO monitor, and some controls for the fridge. If you do check your amps/milliamps with nothing on, then report back here and some of the experts can weigh in on your problem.
 
John From Detroit said:
your batteries are closer to 150 amp hours at the C/20 rate and you can only use about 34-40 before they start aging very fast.. 5 Mpas times 8 hours your batteries are DEAD when you wake up

A pair of GC-2 Golf car batteries should fit in the same tray. They are however TALLER.. The pair, wired in series gives around 220 amp hours (210-250 depending on specific  sub model, mine are 230) YOu can safely use HALF that's over 100 amp hours. nearly 3 times the power you have now, before fast aging sets in.

NOTE they do take longer to recharge too.

I think John is pinning it down quite well.....
except I'll say that 5 amps x 8 hours.... your batteries may not seem dead, but that puts them close to the magic "50%" rule of thumb that so many folks use as the theoretical bottom before doing permanent harm to your battery.....

John, where are you getting the 34-40 amp usable range?

The point is these lead acid batteries don't like deep discharges
the true deep cycle golf cart types can take more than the marine/rv/hybrid type
Actually Trojan specifies that you can take them down quite a bit more than 50%....don't recall the number just now....
but again, the overlying point is don't take them down low if you want them to last.

In my experience, dropping them down just a time or two will noticeably reduce capacity
taking them down to zero once will pretty much kill them.  You might be able to get them to take a charge after once, but they won't hold much. Take them to zero again pretty much sure to be dead for good.

Lead acid batteries will self discharge in storage, even when nothing is connected.  Drop several percent each month.  Doesn't take too long for them to get down to the magic 50%
Leave a light on or something.... it'll kill a battery

Anyway, I think you have too big of a draw for your batteries
and
I'd bet that your batteries are at least partially compromised and no longer hold full capacity.

Once you sort it out, invest in a mechanical disconnect switch at your battery post to protect your new batteries.  Disconnect them any time you store it after charging them of course....
 
I agree with the others and there are a combination of factors at work here.

1. Your battery capacity is less than you think. 2x Group 24's would be a max of about 170 AH and you get that much only when discharging at an extremely low amp rate.  You didn't mention the battery voltage in the mornings, but "flickering bulbs" is necessarily all that low. Led bulbs flicker when voltage gets even slightly low, maybe as little as 11.9v, yet that corresponds to about a 45% charge level. Realistically, though, 45% is about as low as you want to go because routinely driving it down lower than that causes long term deterioration of the battery.

2. A steady 5A load over several hours is nothing to sneeze at.  Also, is the 5A rating @ 12vdc or 120vac? It makes a big difference. I think it is probably @ 12v, but wanted to be sure.

3. You will indeed have what are known as "parasitic loads", things that drain power over time. The LP gas detector is one, and you probably have a CO detector as well. If the fridge is left on, its control board also uses some 12v. None of them is large, but it adds up and runs 24/7.  You can measure it with the ammeter on an inexpensive digital VOM. If you don't have one, they are available for as little as $5-$7 at Harbor Freight stores.  Connect the meter amp probes between battery ground (negative)post  and the chassis ground connect wire to see how many amps are flowing.

4. People often have more power draws than they realize, e.g. cell phones, computers, a night light, a clock, etc.
 
sadixon49 said:
If you are convinced that something is wrong, and you are using too much battery with nothing on, then you must shut off everything, disconnect the batteries, negative lead only, then hook up a meter from the negative lead back to the battery set to read amps. Most any VOM will read up to 10 Amps, so get one and hook it up to read amps between the negative lead and the battery. This will tell you how much current you are actually using, I would expect 20 to 30 milliamps with nothing on, any more than that I would start looking for a problem. Keep in mind there are a few things that stay on and use 12V power even when everything is turned off. Chief among them are the LP/CO monitor, and some controls for the fridge. If you do check your amps/milliamps with nothing on, then report back here and some of the experts can weigh in on your problem.

Thank you!  This is exactly what I was looking for!  As soon as we hook things back up in the spring I will do this.  I AM convinced something is wrong based on the experience of my friends and our very small trailer with no entertainment systems or other frills. Thanks for the response!
 
I note your comparison to your friends' battery life.  What batteries are they using?  You may be comparing apples and watermelon!

When you do your amp draw check, turn off all breakers and pull all fuses to get a baseline draw.  Then turn on breakers and replace fuses one at a time, and note any amp change.  This should at least identify all suspect circuits.

As noted by others, the batteries will lose charge, even without being connected to anything.  A battery minder to keep them charged over winter is a must!  Leaving the camper plugged in would accomplish the same thing using the camper converter.
 
Do you use a battery Hydrometer to check the specific gravity of the battery fluid to be sure the batteries are fully charged?  You could have single bad cell in which would cause the problem.

Even with new batteries in July, if the trailer was stored even with a little tiny 1 amp draw, that is 24AH a day, in a week of non use you have a mostly dead battery bank.  Plug it into shore power for even 24 hours and it still is not fully charged.  Only plugged in for 6 hours and you are starting out with a dead battery.

The biggest issue with the batteries is getting them charged.  The typical inexpensive converter in trailers, used to keep the battery charged, will take 24-36 hours to fully charge a battery discharged down to 30-40% or less full.  Also charging from the tow vehicle while driving doesn't work w/o significant modifications.  The wire size from the tow vehicle to the trailer is much to small.

About the CPAP, my wife uses a Resperonics (sp?)  System One CPAP.  With the humidifier heater off, it pulls about 1 amp or 8-9AH over night.

As stated in an earlier reply, check the amp draw on the battery.
 

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