Eberspacher Parasitic Drain On Leisure Battery.

[Skyliner33]

The percentage reading of BM2 is meant to give rough estimate of SOC of a battery being at rest for hours.
I would suggest let the battery be undisturbed over night and see the voltage reading then. Voltage of lead acid batteries sag even under small loads but bounces back at rest (up to 12 hours after disconnecting the load).

OK, it was left undisturbed overnight. I checked the BM2 last thing at night and this morning. Any suggestions please? The fuses are pulled from the Eber loom. I guess next step is physically disconnect the Eber loom from the leisure battery.

The BM2 suggested the battery recovered by 20% then overnight lost 10% again. Damn this is frustrating.

 

[bullracing]

Are you also testing with a volt meter or solely relying on the app? Lets not forget we are talking leisure battery not starter battery so it can drop deeper. I find the voltage drops loads when I am using stuff but takes about 2hrs to come back up slightly. Something is not right here or you are getting mixed messages from the app. Ignore the red colour, that makes it seem dangerous. I would be checking the app but also getting the volt meter on it.

Personally I am thinking you need to be chargng the battery at a higher rate. It should be floating at 13.7v ish after a good charge. Your 12.8v is good but to me that shows its not had a good high voltage charge very recently, just had trickle charges so I would be getting the voltage down low and then charging at a much higher voltage for a long period. Heres an example of what I am trying to explain.

My 300w solar will charge both my 110ah batteries in a few hours. I dont use my camper very often so it sits outside. The solar will float charge the batteries, similar to trickle charge so it will basicially keep the batterie sat around 12.8v. However when I do take camper out I notice my first night the voltage drops pretty worryingly low 12.3v. I have a CBE digital volt meter, nothing fancy. However then next day when the solar charges the battery it is charging it at a full 14+v and that night with everything running I struggle to drop the battery below 13.3v. What I am trying to say is the battery is not being cycled correctly from what I can see so your not getting a full charge battery to play with.
Mine will stay at 13.5v for pretty much all day with nothing on.

Have you had the battery tested? You could get a local motor factors put their machine/testers on it as it may have lost its charge. We are basing everything on the battery only being 6 months old so perfect however it could be the battery at fault here not holding its charge. The ebers should not be causing you these problems and it should be holding at a constant voltage overnight. To me you need to check the battery or cycle it correctly.

PS. You have to delete all the piccys below your post message box then it will remove the picture. I usually delete all pictures from the upload a file section and start again if one goes weird on me.

 

[Grim Reaper]

How is your leisure battery being charged by the van? Split charge relay or DC-DC charger?
I would disconnect everything except the charging circuit from the leisure battery, then go for a good drive to get the leisure battery fully charged (or connect a mains battery charger to the leisure battery to get the same effect) then put an ammeter in the positive lead off the leisure battery (remove the fuse-I'm guessing you have something like a 50A-100A fuse in the positive lead off the leisure battery-and connect the ammeter where the fuse would have been) start off at 10A scale and move down if the readings are low enough.
Take all the fuses out of your leisure battery fed fusebox (lights/heater/fridge etc.)
Check for current drain with nothing switched on, your BM2 should only be taking a couple of milliamps so anything above that would suggest you have a drain somewhere in your wiring, if nothing is seen, add fuses one at a time and see what affects the meter.

 

[rod_vw]

I'm interested in the outcome of all of this. I've fitted and used Eberspachers of many versions over the past 20 years and never had problems like this.
My current set-up is a D2L Airtronic with 801 modulator set to use the room temperature sensor all fitted new three years ago. The supplier was H. Bowers on S on Trent as a plug & play kit (extra wire installed in loom by me for the room sansor).
I've a 100W solar panel, twin leisure, RING dc-dc charger all on a 2016 T6.
Never any noticeable battery probs.
@Skyliner33 if you need any comparison figures give me a call.

 

[Grim Reaper]

Those charts showing battery voltage over time, the first one doesn't look like it ever reaches a level that the battery could get a good charge from, most lead acid batteries are happy with a charge voltage up at 14.4v max to be able to get some absorbtion, I suspect your battery is not charging properly.

 

[Skyliner33]

Thanks for the replies.
I will read again when home from work and give a more detailed answer. I had a small voltmeter connected to the leisure battery (now disconnected) and it agreed with the BM2. I have done some tests with my DMM and that reads the same.
The leisure battery is charged by a Redarc 1240D from @travelvolts.
When I get home I will try a few more of the suggestions.
@rod_vw thanks for the offer I will pm you later.

 

[mmi]

The fuses are pulled from the Eber loom. I guess next step is physically disconnect the Eber loom from the leisure battery.

The leisure battery is charged by a Redarc 1240D

May worth to check actual current draw of the DC-DC charger? The spec sheet has the following though doesn't specify wherefrom (starter/leisure batery) the no load/standby current draw is.

 

[Skyliner33]

May worth to check actual current draw of the DC-DC charger? The spec sheet has the following though doesn't specify wherefrom (starter/leisure batery) the no load/standby current draw is.
View attachment 54369

Thanks, I've spoken to the vendor of the Eberspacher and his supplier who both have been helpful. Both said they have never heard of the Eberspacher draining the battery, and both independently have said it would be a dead cell in the battery. I need to get the battery tested now. I went to KwikFit on the way home and they wouldn't test a leisure battery. (I also asked about Hunter alignment check - and the wouldn't touch a lowered van).

Both people I spoke to also said the control of the Eber is intelligent enough that if there was a fault in the loom causing the drain it would show on the display (no faults show). I now am beginning to believe it is the leisure battery itself. I have contacted the place I bought it from and am awaiting reply.

Suggestions for places that can test a battery would be appreciated as I've never has one tested before.

 

[bullracing]

Got mine from Leisure Battery - Cheap Leisure Batteries - Express Next Day Delivery - Alpha Batteries

You will need to select the correct battery profile on the charger too which I expect you have already done?

 

[Skyliner33]

Got mine from Leisure Battery - Cheap Leisure Batteries - Express Next Day Delivery - Alpha Batteries

You will need to select the correct battery profile on the charger too which I expect you have already done?

Thanks and yes. Im going there shortly to have my battery tested.

 

[GavinKit]

Sounds like a battery and/charging issue

 

[Skyliner33]

Well I dropped my battery off at Alpha Batteries to be tested and the sent me away with a brand new battery to use whilst they tested it.
I've connected it up to the Redarc, the BM2 and the Eber but nothing else. Ran the Eber for a 30 min test first thing on Monday morning.

This is the profile from the BM2.



And from yesterday:

I am now sure it was not the Eber causing a drain.

 

[Skyliner33]

Now I'm waiting for Alpha Batteries test results.

@rod_vw looks like it was either a duff battery or something in my LED lights. I will test these circuit by circuit as I reconnect 1 by 1.

 

[Bigsidavies]

@Skyliner33 what was the outcome of this Jon?
I’m having this exact issue with my Planar diesel heater. My BM2 plot is virtually identical.
Was it the battery in the end.

 

[Salty Spuds]

I have the BM2 on my starter battery & tbh I don’t trust the accuracy of it. It’s handy as a guide/indicator, but I wouldn’t trust it for any meaningful diagnostics. @Skyliner33, have you had a decent multimeter across the battery & compared the readings from the BM2 & the multimeter?
Don’t forget that the BM2 will also have a parasitic drain too.

 

[Skyliner33]

I have the BM2 on my starter battery & tbh I don’t trust the accuracy of it. It’s handy as a guide/indicator, but I wouldn’t trust it for any meaningful diagnostics. @Skyliner33, have you had a decent multimeter across the battery & compared the readings from the BM2 & the multimeter?
Don’t forget that the BM2 will also have a parasitic drain too.

it’s an old thread. I sold the van ages ago.

 

[Salty Spuds]

it’s an old thread. I sold the van ages ago.

 

[DaveCrampton]

Now this is not recommended, but my friend added an isolation switch to his heater. He doesn't turn it off until it has completed the power down sequence but it certainly isolates the heater from the battery so can't drain and current when off.

 

[Bigsidavies]

Now this is not recommended, but my friend added an isolation switch to his heater. He doesn't turn it off until it has completed the power down sequence but it certainly isolates the heater from the battery so can't drain and current when off.

That will ultimately be my plan. Wire it in to my control panel so I can switch it off using the panel.