Battery life

[Honefree]

After fully charging my battery it seems to drain after just a few hours of running fridge and ceiling fan. Thought it would last a lot longer. Not using water pump, lights or anything else.

Anyone know is this normal?

[phantomjock]

A few details would be helpful:
1. Size, Number, and Type of battery/batteries in bank
2. Age of battery/batteries in the bank
3. Type of refrigerator (3 way/compressor)
4. Which battery House or starting
5. Any modifications to the OEM setup

Sorry for the list - it could be longer, but those few details would be helpful.

Cheers - Jim

[dbaronvt]

We have a 2022 Winnebago Solice Pocket that we got in February. We're having a similar problem: batteries draining in just a few hours with only the fridge running.
Hear are our details:
1. Size: unknown, Number: 2 and Type of battery: AGM
2. Age of batteries: believe their original so 2 years
3. Type of refrigerator (3 way/compressor): Nova Kool model 4400
4. Which battery: House
5. Any modifications to the OEM setup: Not that I'm aware of.

[GallenH]

Unless there's something that I'm not aware of (always possible): Are you sure about that model number. I don't see any in NovaKool's catalog with that number. R4500....yes. 4400...no. And I'm confused by the "3-way/compressor" description. 3-way normally designates a fridge that runs on AC-DC-Propane. Running on propane means it's an absorption fridge and not a compressor fridge which runs on AC-DC. You need to know your house battery size. You say it's 2 batteries. Get their mfg/model off the case and look them up.

[hbn7hj]

You need a shunt type battery monitor to figure it out. Bogart makes one as does Victron.

You need one anyhow for day to day battery management. Get one.

[dbaronvt]

Greetings,
Let me correct a couple of things that were causing confusion:
1. Our Nova Kool fridge is a model 3100 12v AC/DC. It is designed to shut off when available voltage drops below a certain level (10v I think). That seems to be what's happening (not the battery completely dying). But it's happening after only a couple of hours.

2. Our house batteries are lead acid (Wet), not AGM. Brand name is Napa. They're up under the van so they're hard to get to for further identification.

3. If I'm understanding the error codes on my solar charger display, only one battery is working. It shows normal charging and usage on Batt1 but an error code indicating Batt2 is not connected. This could be the whole problem.

Thanks

[phantomjock]

Can't - so won't - speak to your solar monitoring.

Here is a screenshot from the Brochure for the Solis/Pocket (may be helpful):


Group 31 Wet Batteries have between 100-130Ah capacity. So, your house bank will provide about 100 Ah use before hitting the 50% Depth of Discharge.

The Nova Kool 3100 consumes about 2.1 Amps while running. Start up may be more. Unless the batteries are toast, and in reasonable condition and health - you ought to get 40-ish hours of running time on the house bank. Not your experience.

My 1st Guess is Connections (including Grounds). Is Batt1 the starting battery? The House Bank (in my experience) is best wired in parallel to act as a single battery. If you solar is not charging it, is the alternator? Generator? Do you know if the House Batteries are charged/charging with other charging sources - or have been assuming so? You mentioned a reading showing an error - Batt2 not connected. Could be a simple fix - but may require you getting to the connections.

Do you have access to a clamp-on ammemeter? That might help prove if you have current flowing to the House Bank. Then, I'd check to see if the alternator is charging the House Bank. You could even check to see if the Isolator is passing the charge as it should.

When the refer shuts down - are you able to start the van?

My Mantra: 99.99% of electrical problems are Mechanical in Nature. The other 50% are switch errors.

Best of luck!

Cheers - Jim

[dbaronvt]

Thanks again for the reply. This has been a big help. Especially your point about expected runtime on our battery bank. We're definitely not getting 40ish hours. Also I like seeing the formula. I'm really new at all this so every thing is new to me and it's mostly all helpful.

Clearing up a couple more things: 1) the van has two house batteries wired in parallel and one car battery; 2) the solar panels charge the house batteries. Don't know about the car battery; 3) the house batteries may be AGM (not Wet) because solar charger may be set wrong; 4) in talking with their support folks, it appears there may also be a problem with the fridge. They're sending $25.00 worth of parts to fix that.

We now have an appointment for later in the month to replace the house batteries.

Thanks again

[booster]

Wet cells under the van are a tough deal if they are the kind that you can add water to.


The Napa gp31 is a marine starting battery with no caps so low water version. Not in the same ballpark as true deep cycle batteries that would need watering you can't do. It is an East Penn manufactured battery it appears and they make very good batteries but no marine starting battery is going to hold up in that application. The Napa also has a terrible rating on their site so they are probably being used in many poor choice applications.



Probably best to switch to a decent pair of AGMs that will probably last longer than the new wet cells will and they will also perform better with faster charging and better high current use.



Underbody locations can be hard on batteries as they can be subject to some quite high temps from engine, trans, and rear axle heat (if rear drive). High temps shorten all battery types lives.

[dbaronvt]

Our local Blue Compass is putting together a quote for AGM and lithium ion replacement so we can compare. This thread has been a big help as I learn my way through the intricacies of van ownership. Thanks.

[phantomjock]

Be sure to take a deep breath and sit down when they hand you the estimates!

AGM and LiFePO4 Battery Banks have many advantages over Wet Cells - except Cost.
A lot of information on this forum about those conversions. You'll want to check it out.

Cheers - Jim

[SQUASHMIRE]

If wet cell batteries, part of the diagnosis for me would be to see if they are low on electrolyte. While you are in there you could clean terminals, make some voltage measurements during charging and then periodically while discharging (running a constant load like a fan or a incandescent light bulb). Could learn quite a bit that way.

[Mike Bee]

Running a 3 way fridge on 12 volts will drain a battery in several hours.
Combine that with also running the ceiling fan and this does not surprise me.
Having two batteries will add to the run time.
Agree that upgrading to deep cycle wet cell or AGM battery is better.

We only have one AGM battery and when on the road keep the fridge cooling using 12 volt setting. However if we stop and intend to be more than an hour we turn the fridge off.
It will stay cold if you don’t keep opening the door. Never had any spoiled food or a warm fridge in doing this for several 4 week trips with many stops to sight see.

Mike Bee
‘97 RT 170 P
Formerly 89 VW Westy

[Mike Bee]

To clarify my previous answer, fridge is set to 12 volts with the engine running.
With engine off and not hooked to 120 volts, I.e. shopping ,sight seeing, we turn the fridge off.

Alternatively you could run the fridge on propane while stopped for long periods while not plugged into shore power (120 V).

Mike Bee
97 RT 170 P
Formerly 89 VW Westy

[phantomjock]

Perhaps a simple Mantra you can use:

DCee on-the GO,
ACee on the Pole,
Gas in the Outback.

Cheers - Jim