Battery use when using heating
I have a 2006 Swift KonTiki and we do not use the heating generally however this easter weekend was a bit cold and we desided to use it.
With two hours it stopped and checking through I found that the leisure battery power had gone down to 9.6v and this was the cause of the heating failure.
We were connected to the main and using this power so why the battery drain?
On returning home, the battery had recharged on route and test this again the same result, why is the battery draining when on mains power?
Any help or solutions are welcome and appreciated.
NJ
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Comments
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What kind of heating do you have fitted? The wet, Alde heating on mine, still uses a 12 volt circulation pump, whether on mains or not. I assume the blown air heating is similar, though the Truma in my previous caravan heated the caravan very well without the blown air bit.
What ever kind fitted, it sounds like you've a charging fault if the battery is going flat, even when on main. Have you checked all fuses? Failing that, the charger itself could be goosed.
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In our 2005 Swift van we had a Truma blown air system, using a 12 volt fan. On the EHU fuse unit / charger there was a switch labelled van and car and a central position. If in the car position no 12 volt worked unless the car was connected. In the central position it just used the van battery and in the van position the charger was charging the battery. I occasionally left it in the central position and did not realise until things stopped working that the charger was not engaged.
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the op has a MH so any car switch settings wont apply.
however, sounds like there are a couple of possibilities....
battery totally knackered but gives the impression of being charged by the alternator....
battery is being charged (alternator, ehu or both) but has a large drain in excess of the charge rate and is therefore running down much faster than it should.
some tests need to be carried out....
to test of the charger is actually charging on ehu, put a volt meter across the leisure battery and then plug in the ehu, the reading should rise to 14v+ depending on the charger/settings.
to test (crudely) the condition of the battery, charge it fully (perhaps with an external known working car charger) and leave it to rest for 24hrs, measure voltage, should be 12.7v ish.
repeat over the next few days, a settled (lead acid) battery should stay at around 12.7v.
to check if there is an unexplained drain on the leisure battery, put an amp meter close to the earth cable and the discharge reading should be just a few milliamps....if its a lot larger (say 1 amp or more) this will bring the battery down quickly.
my guess, based on your symptoms, is that the leisure battery is totally shot and cant hold a charge, with even the small drain of the heater fan causing it to go critical.
i take your point about being on ehu and that the 'heating fan should run from the mains' but im not sure this is the case with many MH systems, where the mains charges the battery but the battery still supplies the power.....
good luck.
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Failure to hold charge is a common symptom of a failing battery.
It is also common for batteries to fail prematurely due to not being recharged properly. Your Swift charger will only keep the battery topped up and you should periodically take the battery out and recharge using a proper battery charger. Certainly do this if you have used the battery off of EHU. Modern "smart" chargers will recharge the battery properly but that generation of Swift vans didn't have them.
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....and, as i mentioned in Merves EHU thread, with different battery types (gel, AGM, flooded lead acid) the charger need to perform differently to get the best out of each type.
most chargers wont have any sort of selection mechanism to match battery type, so perhaps (as Hitch says) a regular switch to a 'smart' charger will cover most bases.
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It has been usual practice for ten years or more to fit "sealed" leisure batteries to caravans and Motorhome. To recharge properly the voltage needs to be 14.4 volts then decreasing in a controlled manner. Unfortunately it isn't possible to do this from a conventional charger of the type fitted to older vans and also many current vans. The voltage would be too high for other 12 volt appliances and the charging regime cannot be easily controlled.
Its a nuisance having a conventional charger in the van because every time it is discharged you need to either remove or disconnect the battery and recharge using an external leisure battery charger (preferably a Ctek or similar). Although this is occasionally covered in technical articles and some van manuals it is not common knowledge but IS important.
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Thank you all for your suggestions.
Looks like it will be as suspected, the Battery, it is a few years old and if reading all of your comments correctly it looks like the fan uses the battery, which would make sense if you were running the heating on Gas. I will change the battery and see how we get on.
Thanks Again.
Njay
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you could test it as in my earlier post just to confirm, before spending money on a new one.
however, i think this is where the issue lies but id like to check first.
still, if the battery is old and has been failing gradually, perhaps just cut to the chase....?
good luck.
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The charger on a leisure vehicle is usually both a battery charger and a 12 volt transformer. In view of this it should be possible, when on mains, to run all of the 12 volt accessories without a battery being fitted. Before purchasing a new leisure battery I would suggest you have the battery checked by a dealer as well as having both the charging output and 12 volt output checked from the charging unit.
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