Furnace and battery

John Hammond wrote:
Thanks to all of you have replied to my post regarding our running out of battery power in the middle of the night when the furnace runs. Here is some additional information about our situation:
We’re using 2 year old Interstate 6 volt deep cycle Extreme batteries GC2-CHD-UTL 122 mins+@75 Amps 232 Ah. I have no idea what all that means. The charger is a DeWalt 30 Amp charger. They are charged and used in series. I’ve been storing the batteries fully charged and then topping them off just before a trip. I’ve been thinking they are fully charged because the charger has indicated “flo” which I have interpreted to mean “full”. We store the trailer some distance from where we live so I don’t have access to the solar panel now, but it measures about 6’ wide by 2 ½’ tall in two panels that fold in half for storage. The unit can be placed on the ground and moved to face the sun. There is a direct connection to the trailer that was factory installed. I have no idea what converter is in the trailer. It came as standard equipment installed by Rockwood. I just looked at the batteries a few minutes ago. The fluid level was almost to the top of the cells and required maybe a table spoon of distilled water to cover them. We’ve had this running out of power problem when camping at Bodega Bay on the coast north of San Francisco. Night time temperatures can drop to maybe 40 to 45 degrees Fahrenheit – not cold compared to other places, but cold enough that the furnace is important. We’re often out there for 4 nights of dry camping and need the furnace each night. Anyone have ideas that will help? Do you think there may be a problem with the trailer that needs fixing? Where might we start looking for a solution? Or should we just accept being awakened in the middle of a cold night to turn off the furnace and sleep cold? My understanding of electricity is very limited and dates back to high school and college physics 50 years ago most of which I have forgotten. Please express ideas in language I might understand. Thank you.

with the batteries you have if they are good they should easily get you through at least one night of camping, likely two. The issue could be battery condition.

When we had two 6V GC batteries we could easily go 2 full days in temps in the 40's at night 60's in the daytime using the furnace, interior LED lights as needed, etc. before the batteries were down to 50% charged, 3 days if we ran them down to 25% which is ok with GC batteries. and that was without any solar to recharge.

If your furnace quits the first night IMHO either there is a furnace problem or battery problem or a battery alarm problem. In our trailer there is no low battery alarm. And in fact I have not see any trailers with a low battery alarm.

If the furnace is running and putting out heat, your battery voltage is fine. when the battery gets to low the fan will come on but no propane.

Or is the alarm something like the CO alarm? possibly indicating a CO leak in the furnace?