Battery capacity and propane furnace

[timfromma]

I know this has been probably asked more times than I can count but here goes.

The family and I are headed to Florida next week. According to the forecast, the temperature at our estimated stopping point on night one will be in the low 40's so heat will be needed. We will probably find a Walmart so we will be relying on the batteries to run the propane furnace. I just need some reassurance that a pair of 12V 90AH deep cycle batteries will keep the furnace going for at least 8 hours. I think they will I just want another opinion.

[K2Kevin]

Depending on the size of your unit, room temperature shouldnt be difficult for your furnace and two batteries should be enough power, in a pinch, you can also plug in your vehicle and run the engine to give it a charge. Those portable buddy heaters are great for this.

[timfromma]

I do have a portable generator but I'm reluctant to run it all night in a Walmart parking lot.

[bikendan]

Originally Posted by timfromma

I do have a portable generator but I'm reluctant to run it all night in a Walmart parking lot.

40 degrees isn't that cold.
the furnace shouldn't haven't to run constantly.
two deep cycle batteries should survive one night.

[Jmkjr72]

40 deg just make sure you have some extra blankets. Then I would set your heat and get the camper warmed up above where you want it before you unplug from your tow vehicle assuming you actually have power going from the tv to the tt

[K2Kevin]

We use a heated blanket, only 150watts

[timfromma]

I read that the furnace should only draw around 6A while it's running which is only 72W.

[Jmkjr72]

Originally Posted by K2Kevin

We use a heated blanket, only 150watts

Are these battery powered as they are won't have electricity

[K2Kevin]

Originally Posted by Jmkjr72

Are these battery powered as they are won't have electricity

Nope

[Flybob]

You should be good for one night. Be sure to unplug the TT from TV in case your demand is higher than anticipated as it could drain the TV battery as well ( depends on your TV and if it disables the 12V aux when TV ign is off).

[gectisme]

We have 2 batteries also and did a similar stay at a Cracker Barrel in the 40's and had the furnace set to 64 degrees because we were wondering the same thing. The furnace cycled and we had no issues at all the next morning. We had one of the slides out also, but it probably didn't make much difference.

[bikendan]

Originally Posted by K2Kevin

Nope

Then how does suggesting electric blankets that require shore power, help them when boondocking? [emoji780]

[K2Kevin]

Originally Posted by bikendan

Then how does suggesting electric blankets that require shore power, help them when boondocking? [emoji780]

Inverters work...

[5picker]

I can attest from experience if your batteries are good and they are charged to or near capacity, you'll have no problem getting one night's worth of furnace operation. I wouldn't recommended setting the stat at 80 but 65, no problem. Ive done it countless times successfully.

[timfromma]

Originally Posted by gectisme

We have 2 batteries also and did a similar stay at a Cracker Barrel in the 40's and had the furnace set to 64 degrees because we were wondering the same thing. The furnace cycled and we had no issues at all the next morning. We had one of the slides out also, but it probably didn't make much difference.

Our camper is unusable with the slides closed.

[FollowTheSun]

Low 40s outside during the night ... with everything closed, your inside temperature, without heater, will probably remain about 10-15° higher throughout the night. So, your heater shouldn't run much with the thermostat set at 65°. At these conditions, you should have no problem maintaining a comfortable 65° all night. However, the higher the thermostat setting, the more demand.
Other options to consider: 1. use warmer bedding and only run the heater in the morning when you get up; 2. use a "Mr. Heater" portable propane heater during the night. Mr. Heater, on low, will keep your camp-home comfortable most of the night using one small propane canister. The primary problem associated with Mr. Heater is that you will have increased interior condensation accumulate on your windows during the night.

[johnbryanpeters]

Originally Posted by timfromma

I know this has been probably asked more times than I can count but here goes.

The family and I are headed to Florida next week. According to the forecast, the temperature at our estimated stopping point on night one will be in the low 40's so heat will be needed. We will probably find a Walmart so we will be relying on the batteries to run the propane furnace. I just need some reassurance that a pair of 12V 90AH deep cycle batteries will keep the furnace going for at least 8 hours. I think they will I just want another opinion.

Are your batteries marine dual purpose? If so, they're probably rated by Reserve Capacity-25, minutes to 10.5 V at 25 A draw, not Ampere hours. If so, your capacity of both batteries in parallel is probably on the order of 40 Ampere hours.

[timfromma]

No they are not dual purpose. They are flooded lead acid deep cycle batteries.

[ScottBrownstein]

Set the thermostat at 65. You will have no problem.

[NMWildcat]

2 fully charged batteries, thermostat set low (we set at 60), outside temp above 20 degrees, blankets on bed, no problem.