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Discussion Starter · #1 ·
Hi All,

We've now narrowed down what's happening with our leisure battery (or I think we have!). The battery is fine as long as we don't run the fridge on 12v while we're travelling. Now, I admit I'm hopeless at understanding these things but I understood that lthe fridge ran off of the starter battery, that's why it only works when going along - have I got that wrong? Even so I'm sure it shouldn't deplete the either battery! It charges up again as long as we leavel the fridge off. Can anyone advise, please?

sorry if I haven't given enough info
-H
 

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About a year ago I had a flat battery when trying to start the van, got AA out and they got me going, the consensus was I had turned the side lights on by mistake, didn't think I had, but never mind. Two days later went to start the van and battery as flat as the proverbial again. This time charged it up myself. The only thing that was 'on' was the fridge which had been left turned onto the 12v position, which should not matter as it should not draw any power when engine not running. Turned it off and no problems since that day. About the same time I had a problem with the electric step failing to operate when the engine turned off. My theory is the relay at that side of the van was sticking and causing both problems,all the experts told me it could not happen, but the relay has been changed and I have had neither problem since......touch wood. Realise this is not your exact problem but just wanted to point out that just because it isn't supposed to happen does not mean it doesn't. And yes the fridge will drain a battery very quickly.
 

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Depends on how it is wired.

I had a similar problem on an Autosleeper Trident a good few years ago.

The fridge was wired across the leisure battery, but via a relay that sensed output from the alternator (i.e. the fridge was only in 12V circuit with the engine running).

In theory, if it was in circuit the battery should also be being charged. I arrived at Keswick late one evening with a very flat leisure battery. Finally discovered the fuse in the engine charging circuit to the leisure battery had blown (probably my fault, as I had been tinkering earlier). In travelling north, the fridge had rapidly drained the leisure battery, but the battery wasn't being charged.

I had previously thought the fridge 12v was wired across the alternator circuit directly, not the leisure battery. (if you think about it though, you still need a 12v supply on all but piezo ignition fridges when on site)

If your battery charges up from the engine without the fridge on, it doesn't look like this is your problem. If you're charging from mains on site though (which is what I did)........it may be a clue.

Replacing the fuse in the engine charging circuit to the leisure battery fixed the problem. (you'd need an instruction book, a wiring diagram, or to trace the wiring to find where it is).
 

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Discussion Starter · #4 ·
thanks Helen and RobinHood - as far as I can tell the battery is charging from the engine - we've not had it on the charger for weeks (we use the van most days) and were away for two nights without hookup so I think if it wasn't charging at all it would be flat by now. Tho when we went away we didn't have the fridge on while we were travelling cos there was nothing in it :lol: I just put it on today cos it was hot and we had milk to bring home.

Anyway, sounds a bit complicated for me to check everything :oops: and our manuals are in Italian 8O so as the van is still covered by warranty I'll phone the dealer on Tuesday :roll:

Thanks again for the help
-H
 

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Hi,
You need to check the voltage at the battery with the engine running and with the fridge off, and with the fridge on. it should be much the same at 13.8 volts. This check may highlight the problem and could be a bad connection or even too small a cable size dropping volts along it's length.
. Then check the voltage with the engine off , with and without the fridge switched on. It should be the same. If it drops slightly with fridge on then fridge circuit isolation relay is faulty or indeed may not exist and fridge is wired directly to battery. Good luck as it is no use if you cannot keep your fridge cold when driving.
But as you said is under warranty and dealer should sort out, but if he scratches his head and looks blank you can ask if he has done the above checks.
 

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Leisure Battery

Brambles,
Can you tell me what you need to check the voltage in the Leisure battery.
We want to make sure our leisure batteries, one of which we're buying new tomorrow are fully charged and would also like to be able to check them while we're away on holidays for the month of June.
Thanks
Mary :roll:
 

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Hi Mary,
You can get lots of small cheap LCD (electronic) voltmeters that are adequate for the job. Maplin.co.uk will have a variety and expect halfords and DIY shops also sell them. Come with a couple of test leads and you just hold across battery when you want to check and read the voltage. Also useful for checking all sorts of electrics out of you have a problem. (e.g light bulbs, resistors, relays, diodes etc). You will probably find they are called multimeters if you are doing a search.

http://www.maplin.co.uk/Module.aspx?ModuleNo=25377&TabID=1&WorldID=&doy=28m5

the link is one at Maplins at £12.99 which seems quite good value has a lot of features but you can get them cheaper. Even seen them in the cheapy poundstretcher type shops for a few pounds and will do the job of measuring volts.

Argos and Index both have one at £9.88 .

For the serious DIYer though I would spend a bit more - say about £25 to £30
but you can pay anything up to hundreds of pounds liek the one I have but I do serious design and development work.
Sorry if I am rambling on a bit - just trying to aim reply at all levels or readers but if you have a liesure battery you need some form of meter to check it..
Now you are going to ask me what voltage.
I need George Telford here to back me up on figures,
Charging - 13.8 to 14.4 volts
After charging and sitting for a bit doing nought - greater than 12.6 but a good battery should be closer to 13.

On load or partly discharged (2/3 charge) 12 to 12.6
1/3 charge 11 to 12 v
badly needing charge - 10 to 11 and if below 10 get it charged ASAP as it is flat as a pancake. (batteries like to be kept fully charged). I would not go below about 10.6 volts as you really are into the deep discharge area and it does not do batteries anygood.
Don't lay up the vehicle for storage if the battery is below 12.6. Even then I would charge it for a bit to bring it up and keep an eye on it. If laying up for more than a few weeks it is best to disconnect the battery by removing the negative terminal.

Ok I am getting tired now and time I went to bed - cannot even remember how this topic started..ah yes - fridge discharging battery.
And on subject of checking a battery before you buy it - greater than 12.6 volts.

Jon.
 

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Discussion Starter · #8 ·
Brambles said:
But as you said is under warranty and dealer should sort out, but if he scratches his head and looks blank you can ask if he has done the above checks.
Thanks for the advice Brambles, will do these checks before and after taking it in, that way we should have an idea if the dealer has changed anything!! As it's a fair distance away we don't want to be going backwards and forwards.

-H
 
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