Rapid battery discharge

[Mr V]

We came back from a weekend trip and decided to leave the fridge running on propane with no shore power. I assumed that other than small parasitic loads the only draw would be DC power to operate the propane igniter

I made sure that everything else that runs on DC power was turned off. Within 48 hrs the batteries were flat, both house and engine batteries!

Three months ago I installed a Trickle charger as per previous posts regarding engine batteries not receiving charge when parked for extended periods on shore power.

I'm assuming that the Trickle charger is allowing the engine batteries to discharge along with the coach batteries, but I can't imagine what would cause such a rapid rate of discharge on four house and two engine batteries!

Any advice diagnosing this problem would be greatly appreciated?

[Rex]

Did you leave the Inverter turned on?

[Gordon66]

There are also two small fans in the back of the refrigerator that work on a thermostat. Also, there is a fan inside the frig that runs continuously when the frig is on.

Sounds like the relay that ties the battery banks together for starting boast may be stuck closed. This would cause both banks to run down.

You may also have a bad battery in the group that is causing the rapid discharge along with the above items.

[Mr V]

No, I made sure the inverter was off.

[Mr V]

Monaco replaced the batteries under warranty in Feb.09, but I suppose it is possible to have a bad cell.

[Gordon66]

A couple months ago I bought two new chassis batteries,. After 2 months, one battery had a cell fail. This caused the same problem you are having.