I knew this subject was going to come up as the cold is now upon us
I have just had my Numax 105 amp fail on me twice in 2 days after 4 hours
I draw 35 amps from it each day , it has been bench charged every night since new 13 months ago .
So today cost me just short of £200 to get myself a new Numax 105 and a nice little Ctek MXS 5.0 .
Let’s hope I get a bit longer this time
We have always had good service from Numax, hence the reason why I always recommend them. One thing I have noticed is that they haven't been NCC battery verified so am not sure if they are a B or C class battery.
I have just had to replace my leisure battery which would have been 7 years old in January. It was quite happy to run my pump all day.
I connected it up fully charged to a 9kw diesel heater and started that heater 4 or 5 times over the course of the morning. The last start saw the battery voltage drop to 10.8v.
I ordered a replacement Numax but no one I tried had stock. One tried to supply a class 3 junk battery in it place which I refused. Another sent me a Lucas Supreme which was a class2 battery with a CCA rating identical to Numax. Both Numax and Lucas appear to be manufactured by the same factory as the specs are identical.
As you say, time will tell for both of us whether these batteries are as good as they used to be.
These last few days I have been draining about 20 to 25 amps from my battery everyday so am back to 'bench' charging each night.
I do also believe that a standard leisure battery isn't designed for high current draw from say an electric reel, even although brief, and they fail prematurely. I'm not sure how a starter battery would perform long term with electric hose reels and or diesel heaters. Starter batteries are happy delivering high power for brief moments but don't do well with 'trickle' delivery.
The combo battery is a mix of the 2 designs so we don't expect them to perform perfectly in each role. But I would have expected them to last longer than a year tbh. I'm a bit disappointed to hear you have had to replace yours so soon.