Last time I went away for the week I noticed a ticking coming from my trip switch/fuse box - a Powertpart Power Centre II in my Compass Rallye GTE 5.0 1999 modeI. I then noticed my battery had barely any charge. I hoped that somehow it had briefly failed and the charger had not been able to charge it so took the battery home popped it on the smart charger and it fully charged no problem.
Went away with the caravan again and hoped that on a fully charged battery all would be good. Sadly as soon as I hooked up I could hear the ticking again and as the week progressed charge on the battery dropped.
After lots of research I investigated the fuses (stupidly hidden under the charger and in no way accessible without taking everything apart!) but these are fine.
So my questions are - would people agreed this is likely a failed battery charger (only lasted 18 years, disgraceful!!!) and next question - if I want to replace this does anybody know whether I'd be able to get a same sized model? The charger is a Mec LTD 1214 13.8V 12amp model - will there be a suitable replacement?
The charger may be suspect but you need to test it first before buying a new one as they are about a hundred quid to buy. What you need is a multimeter, remove the caravan battery from the caravan and then connect up the multimeter to the battery terminals. Switch on the mains electric and then take a reading at the meter. This will confirm how many volts are being transferred to the battery from the charger which should be around 13.8 to 14 volts. If the reading is any less then the charger (also called a transformer) is defective. If the reading is satisfactory then the problem lies elsewhere.
Checked the voltage and nothing coming from the charger/transformer. Now I've been sat thinking as the van is so old not too keen to spend a fortune on a replacement really. So if I bought a normal leisure battery charger and wired that onto the battery would that be likely to blow the caravan up?!!!!
If that sounds like it might blow it up I might just buy a battery charger and run the cables into battery box so it's easy to swap them over and top up the battery while I'm out! Although even that would probably start to annoy me and I'd end up fitting a new one instead!!!
If you connect a leisure battery charger up to the battery terminals you won't be able to connect the onboard battery connectors at the same time so you will have to stop the charge then swap over and connect up for 12 volt power several times a day which isn't very convenient to say the least. The onboard transformer was designed so it can constantly charge the battery with instant 12 volt power on demand as required without any hassle.
A proper smart charger is what would be required anyway to avoid over heating of the battery but they don't come cheap so you may as well save the money and purchase the right tool for the job disregard how old the caravan is.
You haven't stated how old the caravan is but I replaced mine on a 1999 model a couple of years ago.
Then I could cut the clips off and just wire the cables onto the battery clips - and mount it under the seat or something so it could charge the battery when needed but also be connected to the van at the same time.
But I get your point with just buying the correct transformer- think my only concern is if I buy the wrong thing or find it too complicated to wire in!!! What did model did you replace yours with?
I removed the transformer and had a look at the label on the outer casing. On it will give you all the details regarding amp rating etc. but the problem was that I couldn't find an identical replacement after contact several outlets online to which they all said the item was no longer available. I then phoned a local caravan accessory shop to which they advised which was the required replacement and had them in stock at just under 100 quid. I took the old unit with me so they could confirm the charger I needed and gave me the correct replacement I needed. It was connected up and worked okay but still did a test at the battery contacts and the reading was 13.8 volts which was evident that the old charger was duff.
It's not safe to charge a battery inside the caravan anyway, that's why they made a compartment to isolate the battery so no gases would be produced in the the living quarters. If you change the transformer and connect up the corrrespong cables you are doing it as it was factory fitted and much safer that way.
I meant I would run the cabling from the smart charger into the battery box and mount charger under the seat but you have given me a very good idea!
I'm very internet based - so I have been trawling the internet for what I could buy, but I've got plenty of caravan accesory places near me so I think removing the transformer and taking it to one of them is a brilliant idea!! Plus it has the advantage that if I find it fairly straight forward to remove then I know it won't be too hard to fit! I'm guessing I won't get the same size model but there's plenty of room to mount it nearby.
My next van project is sorted! Thanks for your help!
I think you would be safer getting a proper unit. The screwfix type is rated at 8 amps. As you say its an older van, so lighting may be a mixture of tungsten and fluorescent (a single 10w tungsten is going to use just under 1 amp alone). If you are off grid and using tv and other 12v appliances, that charger is likely to be working quite hard, which could shorten its like.
So I decided to take the broken transformer out and carefully labelled all the cables which were (I thought) going into and out of the transformer - this was where I made a discovery! The complexity of wires are actually just going into a couple of fuses that were tied onto the transformer so actually nothing to do with it - they were my biggest concern about replacing it because online none of them looked like they had lots of connections
So when I removed the transformer I discovered that it was indeed just a power supply going into it and 2 positive and negative leads going out to the battery - so certainly won't be rocket science to replace!
Amazingly I found on eBay a good quality used multistage transformer which will probably do a better job of charging than my single charger ever did! Incidentally when I open the old transformer a couple of capacitors had blown so probably could have replaced them but figured the multi stage transformer sounded better for the battery anyway!
So presuming this replacement charger arrives I shall fit it this weekend and hopefully be functioning even better than before! Going to fit it in front of the powerpart fuse box rather than inside (since it probably won't fit but will allow more cooling around it anyway)
But I'd just like to say thanks again for all your help and thought I'd update this in case anybody else does it themselves.