Battery challenges

[TheNative]

I know this is kind of remedial but really struggling to figure out what the issue is with our batteries. We have a 2015 Bullet Premier (19' floorplan). The problem is that when we are running nothing but the propane fridge and a very occasional LED light & water pump, the batteries drop below 50% in <6 hours. We have two deep cycle lead acid batteries. They are 2-3 years old. We've tested the batteries with a hygrometer and a load tester and they appear to be fine. We've tested for parasite loads and found none. An RV mechanic tested our fridge and said it is not pulling excessive amps. I think our background draw is 2 amps and that pops up to 6 amps with the fridge running. From everything I have read, we should be able to boondock for 2-3 days with these batteries. Are our expectations out of line or is there something else we should be testing for to trouble shoot this? Thanks for any input!

[flybouy]

Define 2 deep cycle lead acid batteries. Are they 6 v GC2 batteries or two 12 vdc marine combination ( have a cold cranking Amp rating) or something else? Are they original batteries from 2015? Have the batteries been deeply discharged, below 50%?

[chuckster57]

How they are hooked up to the trailer will also affect the performance. The trailer leads should be on opposite batteries if they are 12V in parallel.

[Canonman]

When we are dry camping, we use around 40 to 50 amps a day. We have a small inverter (350w) to run the TV for movies at night and on our last trip to the Tetons we were running the furnace to keep the temp at 63 during the night. Like you the usual lights, fridge and water pump usage.
We use a solar kit to recharge during the day. That's how I know the amp number we are pushing back into the batteries.
I would say 100 amp usage over 2 days would be expected with nominal use and should be doable with a couple of 12 volt 100 A/H batteries.
I'd suggest checking the voltage at the battery about 1 hour after fully charging. Expect about 12.6 volts. Note that number. Then check it at 6 hours and again at 24. If nothing is on in the trailer except the fridge, (assumes you have the standard RV fridge not a 12 volt) you shouldn't have much of a change. Maybe down to 12.5 volts. This should give you a baseline to judge how much the overnight parasitic draw is in the trailer.

[NH_Bulldog]

It sounds like your batteries might be suspect. We can boondock a 3 day weekend with 2 Group 27 Interstate batteries without issue (we just wrapped up our fourth season with them). This includes the water heater and fridge on gas, all interior and exterior lights are LED and also running my CPAP. We typically boondock 3 day weekends at state parks at the start and end of the season with at least two regular boondock weekends in between in addition to our regular camping experiences.

We now have a super-quiet inverter generator that can power the whole camper, plus the AC unit, but we have never had to use it on trips except to power up a family members camper that only had one Group 24 battery.

[German Shepherd Guy]

Like Marshall I would like to know what you mean by "deep cycle". Unfortunately there is no standard in the battery industry so it can mean marine batteries, which are not truly "deep cycle" or something more like a golf cart battery or solar system battery which is indeed a deep cycle battery. If they have been discharged more than 50% too many times that will effect how well they hold onto their charge. If they are a marine battery discharged more than 50% too many times that will really have a noticeable effect especially if they are a couple of years old.
You might consider a couple of solar panels and hook them up to your batteries when you are boon-docking to supplement your electric. Fairly cheap right now and silent to boot.
Good luck.

[TheNative]

Thanks so much! We do not have them attached to opposite batteries so I will make that change.

[travelin texans]

Originally Posted by TheNative

Thanks so much! We do not have them attached to opposite batteries so I will make that change.

Connect battery A + to B+, A- to B-, A+ to power, B- to ground.

[BigBobIa]

Originally Posted by travelin texans

Connect battery A + to B+, A- to B-, A+ to power, B- to ground.

Only if 12v batteries!!

[Old_Stevenick]

There are a couple of threads recently discussing this:

The propane fridge draws 12V power, both for it's control panel, igniter and for a heating element in the door.

It could easily drain Lead Acid Batteries quickly.

Either get LifePo4 batteries, or find a way to disable the fridges heating element.

Search recent posts here for info on that.

[Goinav8n]

Another thing to think about is the preamp for your TV anttena is on all the time. It can be disconnected to reduce discharge but it will be there all the time.

I would switch to a Lithium battery when the time comes. A little more cash but way more run time.

Jeff

[Mike71954]

You would probably have to change your charger for lithium batteries.