RVing in the winter

pnichols wrote:

TwistedGray wrote:

pnichols wrote:
our two large AGM batteries have no problem running the furnace for only 15-20 minutes, total, out of each hour at those inside and outside temperatures

Perhaps the key is a second battery. As I understand, the electric blower dragons out within a few short hours without connection to shore power or running the genny.

If the one battery is, say, a 100 amp hour battery and you start the evening and night with having, say, 80 amp hours of it's capacity left ... then you have about 40 amp hours max that you should run it down overnight.

If your furnace is sized right, and your coach interior is "made night-time small enough" by blocking off some sections, then the furnace might only run about 1/3 of the time each hour. If the furnace blower and it's control circuitry only consumes about 6 amps when the furnace is running, then each hour it would drain about 2 amp hours (1/3 of 6) from the battery.

If you run the furnace off the single battery for around 12 hours each evening and night, then 12 hours times 2 amps per hour means that you've used 24 amp hours out of the battery, come morning (not counting some other real low amperage draws from the battery during that time).

Since you had about 40 usable amp hours in the battery at the beginning of the evening ... you should make it through the night on the single battey.

The above analysis assumes that you start out with a battery in good condition and bring the battery back up to full capacity before each night - using some combination of solar plus generator or solar plus engine idling.

The most worry-free solution for cold weather drycamping is to have as much good RV battery capacity on board as you can fit and afford. I consider our two 12V Group 31 deep cycle 115 amp hours each AGM batteries (for a total of 230 amp hours) as about the minimum capacity for my particular piece of mind. When drycamping I charge them up to around 90% about every other day using one of my five different non-solar ways to charge them.

Yeah, I need to get it back from the dealer after it's been hibernating there for the last week and see how much I drain things when holding different temps.

I just recall reading time and time again that people can only eek out 3-4 hours of furnace use off the battery (at least 19G owners). I don't recall seeing their set-ups though and whether or not they're partitioning areas.

If I can get away with the partition, the window coverings, the screen door window cover (allow sun in during the day but keep air out), and the multiple rugs that would be great. I planned to run a propane line inside and use an unvented radiating heater with both a window and a vent cracked. There's a carbon monoxide detector in the cabin already, so I'm not concerned, and we'll be "manual venting" to be additionally safe(r).

BUT I may still run it without any modification first to see if it's enough; however, I'm not just concerned about the electrical draw on the battery but also that I've read it drinks propane. Of course none of this is firsthand experience, so we will see firsthand and then likely go from there.