Battery life

[TsnTexas]

We have a 2020 Reflection 260RD and I have a couple of questions about the 12 volt system. There is a keyed cutoff in the pass through storage, when in the off position will the battery still get charged while the camper is plugged in to shore power?

[Second Chance]

No - the battery disconnect disconnects the converter/charger from the battery so it will not charge. In addition, there are parasitic loads (CO detectors, etc.) that will continue to drain the battery even with the disconnect switch off. Many folks remove a battery cable or install a true cutoff at the battery.

Rob

[TsnTexas]

Thanks! Other than the CO2 detector it seems like I hear a fan running intermittenly, I think in the fuse panel. A cutoff switch sounds like a great idea.

[Second Chance]

Thanks! Other than the CO2 detector it seems like I hear a fan running intermittenly, I think in the fuse panel. A cutoff switch sounds like a great idea.

The fan you're hearing is likely the cooling fan on the converter/charger. FWIW, batteries - especially flooded/lead-acid batteries will self-discharge over time when not on a maintenance charger. You can leave the trailer plugged into shore power all the time as long as you check the electrolyte level on the battery every month or two.

Rob

[TsnTexas]

I'm considering switching to dry cell, I thinking two 12 volt wired in parallel would be best. Appreciate the feedback.

[sande005]

The fan you're hearing is likely the cooling fan on the converter/charger. FWIW, batteries - especially flooded/lead-acid batteries will self-discharge over time when not on a maintenance charger. You can leave the trailer plugged into shore power all the time as long as you check the electrolyte level on the battery every month or two.

Rob

Oh geez, I hate to seem to contradict Rob, as he is always so spot on with advice. And he's not wrong, but this is something I've posted about before, so here goes...

Yes, they do self discharge when disconnected.
It is a factor of time and temperature. The colder the average temperature, the longer they can be left alone before needing attention.
Here's one chart found on the web:



So, Texas/Arizona in the summer - you may want to think about keeping it plugged in, or getting a Battery Minder or similar trickle charger.
For most other areas of the country - disconnect and forget, unless you won't be using for a very long time.

Here in sub-zero Minn., over the winter, my 6 different Lead Acid batteries are never less than 90% when I check after being off line outdoors from Oct-April.
One I forgot about for a whole year, so it went through winter and summer outdoor conditions, and was still at 80% when I remembered. My boat AGM's are now on year 12 with this regimen! (Yeah, I'm really rolling the dice on those!).
Just make sure before you take them off line that:
a) They haven't been behaving badly before (very short life under normal use)
b) They have been topped off with distilled water, if they are not sealed.
c) They are fully charged before putting them to sleep.
d) They really are fully disconnected.

There's nothing wrong with Rob's advice if it makes you feel more confident. Just make sure to check levels periodically, as it can "boil off" over time when on a charger. Getting low can permanently damage them.
There is a miniscule chance that the charger could fail and overcharge, also damaging them. But this is an extremely rare event.

[TsnTexas]

All good advice, Thanks again!

[hartcentr]

Thanks! Other than the CO2 detector it seems like I hear a fan running intermittenly, I think in the fuse panel. A cutoff switch sounds like a great idea.

Whether you unhook it, unhook it and remove it, or leave it hooked up, you still have to check it occasionally. I just leave mine hooked up, and bought one of these on Amazon.

https://www.amazon.com/gp/product/B07GP1RXYZ

It communicates via bluetooth with an app on your phone, and you can check it anytime you are in bluetooth range, which is easy for me because I keep the RV at my house....I can check it from the bedroom on that side of the house. Here is a screenshot from my phone showing what my RV batteries read right now.




Best $30 RV purchase I have ever made. I don't worry about parasitic loads, I just keep an eye on it and top the battery off once a month in the winter. I never let it get below 12.5 volts, but I could let it go as low as 12.3 volts before it would count as a deep cycle. I have AGM batteries.

BTW, it's also a much better way to monitor the batteries while dry camping than the next to worthless battery monitor in the convenience center by the main entry door that the factory installs. By the time that one shows an issue, you have likely already deep cycled it.

[IBEW Sparky]

@hartcentr

Thanks for that link... I just added it to my shopping cart. Christmas has come and gone but I have a birthday coming up soon!

https://www.amazon.com/gp/product/B07GP1RXYZ

[xrated]

Oh geez, I hate to seem to contradict Rob, as he is always so spot on with advice. And he's not wrong, but this is something I've posted about before, so here goes...

Yes, they do self discharge when disconnected.
It is a factor of time and temperature. The colder the average temperature, the longer they can be left alone before needing attention.
Here's one chart found on the web:



So, Texas/Arizona in the summer - you may want to think about keeping it plugged in, or getting a Battery Minder or similar trickle charger.
For most other areas of the country - disconnect and forget, unless you won't be using for a very long time.

Here in sub-zero Minn., over the winter, my 6 different Lead Acid batteries are never less than 90% when I check after being off line outdoors from Oct-April.
One I forgot about for a whole year, so it went through winter and summer outdoor conditions, and was still at 80% when I remembered. My boat AGM's are now on year 12 with this regimen! (Yeah, I'm really rolling the dice on those!).
Just make sure before you take them off line that:
a) They haven't been behaving badly before (very short life under normal use)
b) They have been topped off with distilled water, if they are not sealed.
c) They are fully charged before putting them to sleep.
d) They really are fully disconnected.

There's nothing wrong with Rob's advice if it makes you feel more confident. Just make sure to check levels periodically, as it can "boil off" over time when on a charger. Getting low can permanently damage them.
There is a miniscule chance that the charger could fail and overcharge, also damaging them. But this is an extremely rare event.

The issue with FLA and AGM and even LFP batteries to some extent, they all self discharge some amount. But the RV application adds parasitic drains on the battery and those would be considered, anything that doesn't lose power when the trailer battery disconnect is turned off. Most newer trailer have all kind of electronics onboard and some of them are in fact disconnect with that battery disconnect but some aren't and those, combined with battery self discharge will get you a dead battery in sometimes as short a a week to 10 days.