Leisure Battery

[Steve Gully]

Can anyone out there help us please

We own a Hymer Motorhome and have recently been suffering from a dead battery in the habitation area. This could be replaced but I don't think it's as simple as that as it works ok once our motorhome has been hooked up for a couple of hours.

But then as soon as the hook up is taken off a red light flashes on the control board indicating that the leisure battery is running low

I have checked the fuses in the dashboard and the electroblok and they are all fine I.e. Nothing blown

Appreciate any help, thank you

[Alanb]

Steve,

 

Firstly have you checked the voltage directly across the leisure battery terminals, with the battery on charge.

I would expect to see up to 14 volts in this situation. What sort of battery is it? Main types are Flooded Lead Acid (FLA), Absorbed Gas Mat (AGM), or GEL. If FLA there will probably be removable filler caps. Wearing eye protection, check the electrolyte level. Is it visible above the top of the plates?

Another possibility to consider is the possibility of a high resistance loose, or corroded connection in the battery wiring.

 

How old is the battery? Life varies according to use, and make.

[Steve Gully]

Hi Alanb

Thank you for that, I will have to check the battery type & voltage at the weekend as the motorhome is stored away from home

Steve

[Derek Uzzell]

Steve

 

Historically Hymer have fitted Exide gel batteries for ‘habitation’ purposes. (Example in attached photo)

 

This type of battery cannot be maintained and its contents cannot be checked. Gel batteries have a good reputation for longevity but they are not immortal and, when a gel battery finally fails, it can do so suddenly and completely.

 

Even if a battery is essentially 'dead', connecting the motorhome to a 230V hook-up can normally revive it temporarily, but as soon as the vehicle is disconnected from the hook-up and a load is applied to the battery (eg. blown-air heating is selected) the battery’s state-of-charge will ‘crash’. This sounds like what’s happening in your case.

 

Battery-related advice can be found here

 

http://www.campingandcaravanningclub.co.uk/helpandadvice/technicalhelp/power/a-guide-to-leisure-batteries/

[StuartO]

It sounds very much as though your leisure battery is knackered and so the sooner you replace it the better.

 

One of our resident experts on here strongly recommends not putting your Electroblok at risk by hanging on with a moribund battery, lest you overload the charger inside it.  Even Exide batteries are cheaper than replacement Electrobloks.

 

The same expert has a thing about Bosch S5 (or Varta Silver, same thing but cheaper) as excellent leisure batteries at about £75, a lot cheaper than Exides.

 

Take care to follow the instructions when you disconnect, also to avoid damage to the Electroblok.

 

[Len Salisbury]

Thank you Derek for that very informative link for batteries.

[hallii]

Leisure batteries are special and expensive beasts. There are some cheap batteries marked "leisure" or "deep discharge" but they are little more than cheap car batteries.

 

If you want reliability over maybe ten years or more, buy a good brand gel battery. gel batteries do not need maintenance, and this is important, at least on my Hymer, the batteries are hidden away in hard to reach places.

 

Good brands are Varta and Bosch (essentially the same battery) there may be others just as good, but I have used these for years.

 

H

[Derek Uzzell]

As hallii highlights Hymer have been known to install the habitation battery very inaccessibly, in places where it’s unrealistic to ‘service’ the battery (and may even be a real challenge just to replace it). Accessibility will vary from Hymer model to Hymer model, but wherever it is installed a gel battery needs no venting and no maintenance.

 

This earlier forum discussion may be of interest

 

http://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Changing-batteries-on-a-Hymer/39281/

 

An Exide 80Ah gel battery (or the Sonnenschein equivalent) is likely to cost around £160 (examples here)

 

https://www.tayna.co.uk/ES900-Exide-G80-Marine-and-Multifit-Gel-Leisure-Battery-P7693.html

 

https://www.tayna.co.uk/SL75-Sonnenschein-Gel-Leisure-Battery-P3626.html

 

If a Hymer has a gel battery and it were intended to fit a Flooded-Lead-Acid type instead (eg. the Bosch/Varta batteries StuartO mentions) it would (normally) be necessary to alter the battery-charger’s setting from gel to FLA. The reverse would also be true - if a Hymer has a FLA battery and it were intended to fit a gel type instead, it would (normally) be necessary to alter the battery-charger’s setting from FLA to gel.

[Brian Kirby]

Steve Gully - 2016-03-03 7:04 PM

 

Can anyone out there help us please

We own a Hymer Motorhome and have recently been suffering from a dead battery in the habitation area. This could be replaced but I don't think it's as simple as that as it works ok once our motorhome has been hooked up for a couple of hours.

But then as soon as the hook up is taken off a red light flashes on the control board indicating that the leisure battery is running low

I have checked the fuses in the dashboard and the electroblok and they are all fine I.e. Nothing blown

Appreciate any help, thank you

What you describe, as others have said, is symptomatic of a gel battery at the end of its life. However, you haven't said how old the van is.

 

If it is less than about 6 years old there may be an additional problem. If less than 3 years old, an additional problem would seem more likely.

 

If you bought the van new, have you ever changed the battery? If so, did you change like for like?

 

If the van was not new when you bought it, do you know if the battery has ever been changed?

 

If the battery is the one Derek illustrated (or the almost identical Sonnenschein), it is quite likely to be the original, so will probably be the age of the van.

 

Our van (new 2013) was fitted with a Banner AGM battery from new, so if you find one of these it may be original fit. If of another make, it may indicate that a replacement battery has been fitted. If so, you would be well advised to verify what type of battery it is, and if not gel or AGM, to check that the battery type selector switch on the Elektroblock is in the correct setting.

 

For gel or AGM it should be set to "Blei-Gel", and for flooded to "Blei-Saure". The selector is recessed to prevent accidental movement, and will probably require the tip of a ballpoint pen to move. If the selector is incorrect for the battery fitted, and the battery is newish, it will almost certainly be the reason for its premature failure.

 

Do you heavily discharge the battery? As a general rule it is not recommended to run batteries down too far. A new gel battery can be discharged by about 75%, at which level its should read in the region of 12.3V, but should immediately be re-charged, ideally using the on-board charger. If a flooded battery, the discharge should not normally be allowed to exceed 50%, at which point it should read about 12.3V, with the same proviso re re-charging. Exceeding these levels of discharge, or even reaching them regularly, will reduce the life of the battery, as will leaving the battery in that condition for more than a matter of hours. The older the battery, the less resilient it becomes, and the less deeply it should be discharged. Funny things, batteries, as I have learnt! :-)