New battery voltage dropping fast.

[Wrighpm]

Hi all, a few months ago - last Spring I asked for recommendations for a new battery for my moho.
I got lots of help and I went for a Lead-Carbon on from Alpha Batteries.
All seemed good. We rarely use the battery for more than lights, water pump and charging a couple of phones.
Whilst in France for a month we did a mix of Aires, campsites and wild camping. About our 3rd week in the vehicle panel alarmed and turned off all 12v ccts. This was completely unexpected. The battery had dropped to under 11V. We had just driven 100k and had plenty of solar as well so we were surprised.
When the engine was started the battery showed a charging voltage of over 14v. On bright days solar is usually plenty to keep topped up.
We are currently off grid in Cumbria and the battery failed on 2nd day.
Unfortunately whilst in mid-shower I was plunged into darkness. I started the engine to allow me to finish my shower. After 15 min the battery showed about 13V. This seemed to have come up rather quickly? No power used overnight but as it was perishing we put the gas heater on and this uses 12v for fan. After 30 min voltage was showing just over 12.
Not really sure what is going on. If there was a parasitic drain it would surely have gone flat overnight.
Is my new battery rubbed already.
Thoughts please ?

 

[maingate]

I developed a similar problem one time and it turned out that the solar regulator was faulty. Strangely, my ammeter showed a drop in voltage supply to the leisure batteries in sunshine and a small rise when a cloud obscured the panels. It was very odd but you might want to check your regulator.

 

[Val54]

Very odd, given your experience in France, it would suggest a charging issue rather than a drain, but maybe do a full charge off the vehicle and check it is holding its charge for starters.