Leisure Battery Issues

[TOAD on Tour]

Hi all, newbie here after picking up our 2007 Hymer B660 SL last week. I am having issues with the Leisure Battery and would appreciate anybody’s advice. Firstly we are really happy with the van, it is in great condition for its year and has lots of service history etc. However upon collecting the van, I did notice the leisure battery charge % on the display panel was around 25% and no solar was feeding the battery either (it has 2 original solar panels on the roof). I drove it home which was around 120 miles and the leisure battery went up to 75%, so I thought all was well. I have since had it on EHU on my drive and as we have been pottering around inside the battery is now down to 8% left even though it is on EHU (EHU is working as we have been using one of the plug sockets etc). I have reset the electric (is it the MCB or something!), the solar is not pulling in any energy still and 1 of the 3 pin electric sockets is not working (not sure if that is connected to these issues). On the display panel, when on hook up the battery is showing between 13.6 - 14.4V and when I disconnect the EHU it drops to around 13.5V (Definitely stays above 13.0V). I am thinking that it must be something to do with the charger as I believe the engine alternator charges the leisure battery when driving, which seems to be working? But when on EHU it does not charge and the solar is not charging either?
Any words of wisdom or advice would be appreciate......finally, I can barely change a lightbulb, so please treat me kindly!!

 

[paddymcc]

I had a garage check the voltage and that seems fine, they seem to think the voltage is not generating the amps if that makes any sense?

It makes sense if the batteries don't hold their charge. They appear to charge fully and get to 13+ v but as soon as you apply a load they drop to 11v ie flat. So you need to do Lenny HB test with the fridge again and check the voltage with a voltmeter after the load ( ie fridge) has been disconnected.

 

[TOAD on Tour]

So...I ran the fridge for 30 minutes at it was drawing around 13.1a. When I switched the fridge off the voltage reading was 12.8v.

 

[paddymcc]

Ok to do the test you need to work out the time it takes to reduce capacity by 25%.
I don't know your battery capacity but will assume that it is 100Ahr (and that you only have one battery. As I think you have 2 in parallel then you have to double this)
100/13.1=7.633
This is the time to lose 100% of capacity.
7.533/4=1.9 hours.
So you should run the fridge for 1.9 hours and the check the voltage at least 30 min after you have taken it off load.

It should have a voltage at 75% as per Lenny's chart (figures vary depending on type of battery).

Hope this makes sense.

 

[Hymerbrittany]

Waste of time they will do a CCA test which is a starter battery test meaningless for a leisure battery. No one will do a leisure battery test as it will cost more than a new battery as it will take a day or two.
The only way to test a leisure battery is by a controlled discharge test which you can easily do yourself.

First charge the battery fully and leave it to settle for an hour then:-

For example if it's a 100a/h battery load it with a 5 amp load and run for 5 hours, this will represent a 25% discharge. (adjust load/time to suit the size of the battery)
Disconnect the load and leave to stand for at least 30 min then measure the voltage.
Repeat the test and you will have discharged the battery to 50%.
You can repeat again then it will be 75% discharged.

View attachment 441844

I totally bow to greater knowledge than I, but with respect, I did have mine tested on the spot. Perhaps French garages and mechanics have superior equipment for this type of thing. After all, every other French family has a motorhome! If not, then others will offer better advice than mine. Hope you get it sorted.

^{_{Subscribers  do not see these advertisements}}

 

[Lenny HB]

So...I ran the fridge for 30 minutes at it was drawing around 13.1a. When I switched the fridge off the voltage reading was 12.8v.

Need to run it for several hours to get any meaningful results.

I've found my Gels (3 x 78a/h) if I take them down to around 75% they still sit at over 12.7v but take them down to 50% voltage is roughly what I would expect.

 

[TOAD on Tour]

Thanks all, ok I have hooked the van up on EHU for the night in the hope that the batteries (2 x 110ah Vartas) should be fully charged by the morning. I will then run the fridge for approx 4hrs based on Paddymcc calculations. More to come

 

[Lenny HB]

Thanks all, ok I have hooked the van up on EHU for the night in the hope that the batteries (2 x 110ah Vartas) should be fully charged by the morning. I will then run the fridge for approx 4hrs based on Paddymcc calculations. More to come

Don't forget to disconnect the solar while testing.

 

[TOAD on Tour]

Thanks Lenny...but don’t get me started on the solar....I don’t think that’s operating anyway!

 

[TOAD on Tour]

Ok...the load test didn’t go too well....I left the fridge/freezer on and after a couple of hours I went to check the status, but the 12v had switched itself off and couldn’t cope with the load, but I am not sure how long it took to do this, as the previous day I did it for 30-40 minutes and it was looking ok. The panel was still showing 41% capacity, but I think this is obviously unreliable and needs resetting when I do sort out the under lying problem. My plan for the weekend is to disconnect the batteries and give them a good charge, before completely discarding the batteries and see what that does. I have purchased the ctek charger but unsure which setting to use, please could somebody advise? Also am I right in saying that the sequence of events in removing the battery’s (2x 110ah) is:
1. cover the 2 solar panels (is this necessary if I am also removing the solar fuses?)
2. Remove the 2 solar fuses
3. switch off the electroblok with the large black switch
4. remove the batteries, taking note of the sequence they are installed
5. charge batteries until the ctek charger is complete or shows an error message etc.
6. if batteries are showing that they are good, install as above sequence in reverse...or purchase 2 new batteries and install

??

^{_{Subscribers  do not see these advertisements}}

 

[autorouter]

Most batteries fail by gradually losing capacity. A failing 100Ah battery might behave like a perfectly good 30Ah battery. It will charge up OK, keep its voltage, but will be quickly exhausted from normal loads. That's why the only real way to check a leisure battery is to charge it up, put a load on it, and see if its voltage falls as you would expect, or faster.

The display shows 41% when the battery is flat. That means you've taken 59% out, and the battery is flat. If it's a 100Ah battery it's behaving like a 59Ah battery. A 100Ah battery is considered ready for replacement when its capacity drops to 80%, ie 80Ah. Some people run them lower than 80%, but that's a choice they make.

 

[TOAD on Tour]

Also....before I start, does anybody think that I am wasting my time doing the above and should just bite the bullet and purchase 2 new battery‘s and be done with?

 

[TOAD on Tour]

Thanks autorouter, the reason I think the panel is telling porkies is sometimes it says 100% and other times is says 50%, even when it has been on EHU for sometime. I read other posts about the panels playing up if they have been left off etc. I have only had the van a couple of weeks, but I do not think it had been used for sometime before I purchased.

 

[autorouter]

If the batteries are failing by losing capacity, the CTEK charger will charge them OK and they will behave like perfectly good batteries with a lower capacity. If you do the test, at least you will know that. If there are other more definite battery problems this test might show them up.

 

[TOAD on Tour]

Thanks, do you happen to know what charge setting I put them on?

^{_{Subscribers  do not see these advertisements}}

 

[Lenny HB]

You haven't said what type of batteries but at 110a/h I assume standard flooded cells so it shouls be the standard lead acid setting.
Whats wrong with using the EBL to charge them?

Also....before I start, does anybody think that I am wasting my time doing the above and should just bite the bullet and purchase 2 new battery‘s and be done with?

I think I would just get a coulpe of new batteries preferably Gels.

 

[paddymcc]

Don't forget if you do disconnect them do it in the order negative terminals first then positive terminals and make sure that the terminals can't short by insulating them.

If you are separating the two batteries you can do the discharge test on each one separately. (Although if they are the same age there is a good chance both are failing. Do they have a date on them?)
I think that you are likely to end up getting new ones...

 

[TOAD on Tour]

Hi - thanks for the replies, I have them now on charge on the recondition setting on the ctek. I have to admit, I am thinking of just biting the bullet and getting 2 new batteries as I am only going to have to do the load test etc. Again when they are fully charged. The reason I have them on charge vs the EBL/EHU is that the control panel is definitely telling me wrong info at times I.e. 50% charge one minute and 100% the next and that when it’s not on EHU and I have nothing switched on, so I thought giving them a good standalone charge might be more reliable. But for peace of mind I am leaning more to chucking money at 2 new batteries and then re-programming the panel with the correct ah according to the batteries. My question is, I currently have 2 x 110ah, we would be on EHU most of the time, but will be off grid now and then for 2/3 nights at a time in the summer. All internal lights are leds, we have a gaslow system for fridge, heating etc. when off grid and I have a large standalone battery pack that would power phones, laptop etc. for times off grid. We wouldn’t use the 12v tv off grid as we would watch anything on our laptop via Sky Go etc. Do you think I would be ok with 2 x 90ah batteries based on the above?

 

[TOAD on Tour]

I am just worried that if I buy new batteries that it does not solve the problem and it is something else I.e the EBL etc.

 

[Lenny HB]

We wouldn’t use the 12v tv off grid as we would watch anything on our laptop via Sky Go etc. Do you think I would be ok with 2 x 90ah batteries based on the above?

If you only going to spend 2 or 3 nights off grid then a couple of Varta LDF90's would be fine, make sure the EBL is set for the battery type.

^{_{Subscribers  do not see these advertisements}}

 

[paddymcc]

In the summer, if you get the solar working you should be fine for a bit longer.

 

[TOAD on Tour]

Ok! I now have 2 x new Bosch 90ah batteries installed. i have reset the control panel in the van to reflect 180ah and it has automatically recalculated optimum Life at 144ah (I assume it doesn’t like using the last 20%). I plan on doing the fridge test tomorrow to hopefully confirm the battery‘s are now good etc. My question is that I have the van currently on EHU and the panel in the van is showing the batterys at 100% charged. However it is also showing that only 0.4a is coming in to battery from the EHU I assume. Is this because it is limiting what is coming in as the battery’s are fully charged? I have nothing switched on other than the 12v tv on standby etc. Many thanks as always!

 

[Lenny HB]

The EBL will charge until the the batteries reach 14.2 to 14.4 volts then it will switch to absorbstion mode the voltage will stay at 14.2 but the current will be limited to a max of 1 amp after 1 hour the voltage will drop to a float voltage of 13.8v with current limited to 1 amp.