Battery charger or battery?

[Nukeproof@36]

Hello wonder if anyone can help? we are just on our way back from.10 days in somerset. The van hasnt been finished for very long and this is the first bigger trip out we have done a couple of nights before and everything was fine. So during the 10 day the ac - dc battery charger hasn't been doing what i expected. When you plug in to hook up it comes on and starts to charge the battery however once the battery is full it then stops charging and doesn't start again. The battery has been down to 12v and from my little knowledge that is a fully discharged agm battery. If you switch it off and back on again this seems to reset it and it starts to charge again. It's been working fine for the past 3 years the only difference now is a fridge. So I suppose my question is, is the battery done and needs replacing is the charger faulty or both? I have a black van and its been like an oven this past week so wondering if the heat has made the fridge work overdrive and my system just couldn't keep up or are the electrics at fault? It's a pre made rayne automotive set up so I'd like to think its not a voltage drop issue I dont get any fault codes on the fridge and everything else is working just fine

 

[Salty Spuds]

What battery charger is it? Make/model?

 

[Nukeproof@36]

Rayne automotive supplied it. So no real name and model I dont think. Probably a rebranded one but dont know who makes it

 

[StratosFearXX]

Sounds like the charger's gone faulty to me. Do you have to set it to the right battery type? Could it be it's set to LifePo4 and you have an AGM battery or something?

 

[ginkster]

The battery should be ok as long as you’ve not taken it too far below 12v. I would expect the charger to go into float when the LB is full then back into bulk as the voltage drops on the LB. Either it’s not as clever as that and just switches off, it’s in the wrong mode or has a fault. Do you have an instruction manual?

 

[Nukeproof@36]

No manual, its an agm battery and its set to agm.

 

[ginkster]

It’s either not very ‘intelligent’ then or faulty. I’d try on a different battery if possible and get hold of RA for a manual and clarification on how it works. Maybe you can find a manual online?

For comparison my Victron ip65 would just kick back into bulk from float/storage when it senses a certain (configurable) current from the LB.

 

[roadtripper]

You're correct on 12v being around 50% on an AGM.

Your charger looks like a clone/rebadge of a basic CTEK.

What I think is happening is the additional load of your fridge working hard is making your battery charge much slower than the charger expects - a lot of smart chargers (and my CTEKs do this) will failsafe and cut out until you reset them if one of the stages doesn't complete in a reasonable time - rather than continuing to charge what it thinks might be a faulty battery and maybe cause overheating.

If your fridge is working flat out and pulling 5A and you only have an 8A charger you are essentially only charging at around 3A which is a trickle.

So I wouldn't panic yet, you've got the right battery levels in mind. I suspect as we return to cooler weather you might find it behaves. If so then your best course of action is to upgrade from an 8A charger to something with more headroom - a 15A IP65 Victron should be nearly a drop in replacement if a little larger physically.

 

[Nukeproof@36]

Thanks for the replies. I'll give a bigger charger a go and see how that goes

 

[roadtripper]

How did things work out @Nukeproof@36 ?

 

[Nukeproof@36]

I've not got round to sorting it yet. We aren't going away again for a couple of months so will sort it before then