Batteries Losing Charge

[Nealp49]

I have two, nine month old deep cycle batteries in my 2020 Raptor 423 that are losing charge after 3 or 4 days. I took them to Autozone and they both tested good. I measured the voltage out of my inverter and it was 13.6 volts which is good. Anybody got any ideas what could be drawing my Batts down ?

[Lee]

Hi,

What is the voltage at the batteries while charging?

What position is the battery disconnect switch in?

With the shore power dis-connected, do any 12v appliances work? lights? furnace?, etc

[chuckster57]

You’ll have a draw on your batteries all the time unless you disconnect the trailer at the battery post. Depending on what’s powered, your battery’s will discharge in no time.

If you have a DC amp clamp you can measure the draw and start pulling fuses to see if you can lower it.

[NH_Bulldog]

Aside from what others have said, you mentioned voltage out of your inverter? I assume that you intended to say converter?

A couple of simple questions; when the batteries are running down, are you plugged into shore power or not? Is the battery disconnect in the wet bay turned off? Even in the off position, there are critical circuits that remain energized and drawing power. (gas leak detector(s), InCommand, etc.).

As Chuckster mentioned, the only way to prevent draw with any certainty is to disconnect the batteries, but that is time consuming and a PITA every time you get home or are getting ready to leave. Do you have a way to plug into shore power when parked, even if only on an extension cord from a regular 15 or 20A outlet?

[JRTJH]

If two "golf cart batteries" are discharging that far down in 3 or 4 days, you've likely got something that is turned on that is using that much battery power.

I'd guess that the trailer is not plugged into shore power while the batteries are discharging ???? If it is unplugged, I'd start looking at inverters, things plugged into the inverter powered plugs, and also 12 volt items like tank heaters, fans, etc. If the furnace is turned on (thermostat to heat and even at a 60F thermostat setting, the furnace will turn on even on 50F nights. So if the temperature is falling to 45 or 40 at night and the thermostat is set to heat, that could easily drain your batteries. My guess would be the tank heaters or an incandescent light in a storage area that you haven't noticed yet...

Now, if the trailer is plugged into shore power and the batteries are discharging, you've got a problem with your converter/charger or one of the "DC circuit breakers" in the passthrough (close to where the 7 pin umbilical connects to the trailer.

[Nealp49]

Yes, I'm plugged into shore power. I only turn on the furnace mornings when it's chilly, then off later. No lights found on in compartments. Charger voltage last week was 13.6v. Still scratching my head.

[Nealp49]

13.6v charging voltage. Battery switch on. Shore power connected. When disconnected my 12v systems work fine.

[Nealp49]

I am plugged into shore power all the time. We're full timers. Battery disconnect switch on. Still trying to figure it out.

[NH_Bulldog]

Originally Posted by Nealp49

I have two, nine month old deep cycle batteries in my 2020 Raptor 423 that are losing charge after 3 or 4 days. I took them to Autozone and they both tested good. I measured the voltage out of my inverter and it was 13.6 volts which is good. Anybody got any ideas what could be drawing my Batts down ?

Just to confirm, they are true deep cycle batteries correct? Not standard dual purpose (label has CA or CCA listed), or lithium, or gel batteries?

[ChuckS]

You have a 75 amp WFCO converter that was stock OEM equipment.It is more than capable of maintaining those batteries and running everything else..

If you ACTUALLY measured 13.6 vdc directly at the battery terminals then the batteries are receiving a constant charge from the converter.

I would recheck your measurements....

I would also check the voltage out at those battery cables with them REMOVED from the battery terminals to get a true reading on the converter performance.

If you had a clamp on DC multimeter that measured DC amps you could also read the actual amp draw across the DC BUS system