Is it my house batt. or the guest 5/5 oem charger???

[triton1]

Here is the situation:
C-Dory 25 (2006) at the dock with shore power connected. Guest Bat. Sw. on main only. The main Bat. bus consists of two deep cycle bat., Guest OEM 5/5 charger on line.


My xantrex volt/amp/bat.% cage starting showing unusual discharge in the range of -18.2 amp/hr. discharge with minimun dc equip. operating. The house batt. were very slowly going from 98% to 90%. The bat. charger red light on, indicating charging, however it became hot to the touch and eventualy stopped charging, cooled down and went in to charge mode again.

Charger not charging properly or do I have a main bat. failing?

Thanks

[lloyds]

The charger going on and off because of heating up would lead me to believe you have a battery going bad, internal short. But I am not an electrician so it is a wild guess. Can you disconnect one battery at a time and tell that way?

[thataway]

I would do as Lloyds suggests. Disconnect both batteries to be sure that there is no load. Then observe what their voltage does over several days. It should remain at 12.6 volts on both batteries. If it does, then load test the batteries. You can either put a formal load tester on, or you can put a high load on yourself--if you have an inverter, then put a 500 watt load on it (equal to 50 amps or so) and see what each battery does when under load--check voltage after 30 minutes, and then stop the load, and measure the voltage at 60 minutes. You can also use low level load testing, such as full running lights for 6 hours, and check the batteries then.

I tend to replace batteries in 4 years--or sooner if they do not seem to be holding a charge as well. Some premium batteries will last much longer.

These chargers do fail--but usually it is one or both of the banks which stop charging--not as you describe.

[BrentB]

Darn I missed this Q & A, this site is better than AskIt

What type of batteries do you have?
If wet cells, are they low of water