Running LP Heat On Batteries...

azloafer · 03-10-2010, 12:36 PM

Recently we attempted to get into a popular State Park and it was full. We were told that we could park in a waiting area and could have a site in the morning. There were no hookups in the waiting area and no generators allowed between 8pm and 8am. It was 40 degrees that night. We were afraid to run the LP heat with its fan for fear that the fan would drain the two AGM coach batteries before morning. Was this a valid fear or did we freeze for nothing? Joe

SteveLevin · 03-10-2010, 12:42 PM

I think you froze for nothing -- although you did have piece of mind when in doubt, and that's worth something.

With two coach batteries I can run the furnace all night long and be okay, although two nights without a significant recharge might be pushing it.

Steve

Jim Stewart · 03-10-2010, 02:49 PM

If the batteries are charged and you do not watch 6 hours of TV and run the microwave to make your warm milk before you go to bed, should be OK.

CaptBill · 03-10-2010, 08:33 PM

Let's say worse case scenerio happened, and the coach batteries went dead by morning... you could still start your generator and engine from the chassis battery. That would not have been affected by the propane furnace running on the coach batteries.

That said, 2 charged coach batteies will last through the night, running the furnace and a lamp or 2. If they don't, they may be near replacement time. When you do replace, the battery tray should hold 3 house batteries, which will extend your up-time.

powerboatr · 03-10-2010, 10:15 PM

if in doubt or ME freeze i would have run the engine to charge up the batteries
or the genny, i doubt park ranger would have made a stink in such cold situations...

we ran for 10 hrs on just batteries in 30 F weather last snow storm, they got low but never low enough to be a worry.

Cheryl Bisson · 03-15-2010, 11:29 AM

When we dry camp and it's cold during the evening we use the furnace set at 70 and an afghan. We read (the only lights on) rather than watch TV. Also, we shut the door to the bedroom and bathroom and close their floor heat vents so only the living space needs to be heated. Overnite the furnace is off and we use an electric mattress pad with an extension cord that is plugged into a small, portable inverter (it makes no noise) which is plugged into a 12V outlet in the bedroom. We also have a down comforter, and if it's really cold, we add a blanket on top of that. By morning, the batteries have not dropped all that much and we were comfortable.

2005 Adventurer 33V

RVThere · 03-15-2010, 12:18 PM

One time at Shenandoah I did what powerboatr suggested and ran the engine to charge the batteries in the middle of the night.

Our old class C single coach battery died, it was early April, and the wife and kids were cold. So they may have a no generator rule but the did NOT have a no engine rule!

Make sure you crack a window so you don't have a PERMANENT sleep!

DAN L · 03-16-2010, 12:36 AM

Quote:

Originally Posted by azloafer

Recently we attempted to get into a popular State Park and it was full. We were told that we could park in a waiting area and could have a site in the morning. There were no hookups in the waiting area and no generators allowed between 8pm and 8am. It was 40 degrees that night. We were afraid to run the LP heat with its fan for fear that the fan would drain the two AGM coach batteries before morning. Was this a valid fear or did we freeze for nothing? Joe

my suburban sf42 furnace uses 11.5 amps per hour when the blower is operating. i have 300 amp hours stored in my battery bank although i don't like to use over 150 amp hours. using more than 1/2 capacity is deep cycling and shortens the lifespan of the batteries. i can definitely use the furnace, run the tv with the inverter and lights for one night. 2 nights would be stretching it, but still possible, using less tv, and monitoring the battery voltage more closely.
check these resources:

Deep Cycle Battery FAQ

The 12volt Side of Life (Part 1)

Frequently Asked Questions (FAQ) - DC Battery Specialists

http://www.rvcruzer.com/electrical/tutorial.php

CaptBill · 03-16-2010, 10:51 AM

Quote:

Originally Posted by Cheryl Bisson

When we dry camp and it's cold during the evening we use the furnace set at 70 and an afghan. We read (the only lights on) rather than watch TV. Also, we shut the door to the bedroom and bathroom and close their floor heat vents so only the living space needs to be heated. Overnite the furnace is off and we use an electric mattress pad with an extension cord that is plugged into a small, portable inverter (it makes no noise) which is plugged into a 12V outlet in the bedroom. We also have a down comforter, and if it's really cold, we add a blanket on top of that. By morning, the batteries have not dropped all that much and we were comfortable.

2005 Adventurer 33V

I wouldn't close off heat registers. That can restrict airflow (reduce CFM) over the furnace heat-exchanger, and cause back pressure. That will reduce efficiency; waste fuel. I would leave them all open, and also make sure that the filter is clean and return air grills are not blocked. That will be the most efficient furnace operation.

Insulating the roof-vents (a throw pillow or R-max cut to fit)can also help prevent heat loss.

Chuck 1935 · 03-16-2010, 11:50 AM

Just came back from a dry camping trip and thought I would try using my gas furnace after reading these posts. I have three house, deep cycle marine batteries from costco. We watched a two hour movie on the inverter then shut off the inverter, all the while we had the furnace running all night, cycling on and off. It was set at 68 degrees and was around 50 outside. I checked in the AM and the batteries, at rest, still showed 12.4 volts.
PS... No need to tell me how brave I am for "camping" in 50degree weather!!!

azloafer · 03-18-2010, 01:51 AM

Quote:

Originally Posted by powerboatr

if in doubt or ME freeze i would have run the engine to charge up the batteries
or the genny, i doubt park ranger would have made a stink in such cold situations...

we ran for 10 hrs on just batteries in 30 F weather last snow storm, they got low but never low enough to be a worry.

Actually, the park ranger caught us with the generator on at 7 am when we should have waited until 8am. He had us turn it off! Joe

georgetown350 · 09-27-2010, 06:35 PM

My generator starts from the coach batteries so when they go dead I cant start the generator and there isn't enough battery power to activate the boost switch. It happened today. I assume the only way I would be able to get the generator started would be to run the engine for a very long time in order to charge coach batteries. I didnt run the engine as I was able to plug into shore power.

HotMech · 09-27-2010, 06:55 PM

Quote:

Originally Posted by georgetown350

My generator starts from the coach batteries so when they go dead I cant start the generator and there isn't enough battery power to activate the boost switch. It happened today. I assume the only way I would be able to get the generator started would be to run the engine for a very long time in order to charge coach batteries. I didnt run the engine as I was able to plug into shore power.

Mine used to start from the coach batteries too. I simply moved the cable to the genset, from the coach battery to the chassis battery. Problem solved. I have a Xantrex "Echo Charge" tied between the coach and chassis battery, that is also tied to the solar panels, So I can always start the Genset. BTW The Genset does not charge the battery it starts from.
Kerry

georgetown350 · 09-27-2010, 07:04 PM

Quote:

BTW The Genset does not charge the battery it starts from.

That is an interesting idea about switching the cable so that the chassis battery starts the generator. When dry camping one of the main purposes of running the generator is to keep the coach batteries charged so your statement confuses me?

John Hilley · 09-27-2010, 08:42 PM

Quote:

Originally Posted by HotMech

Mine used to start from the coach batteries too. I simply moved the cable to the genset, from the coach battery to the chassis battery. Problem solved. I have a Xantrex "Echo Charge" tied between the coach and chassis battery, that is also tied to the solar panels, So I can always start the Genset. BTW

Quote:

The Genset does not charge the battery it starts from.
Kerry

It charges the coach batteries when that is what it is started from. The generator feeds the converter/charger for the coach batteries. After you moved it to the chassis battery, your statement is correct. Also if your coach batteries are rund down and you start the engine, you should be able to start the generator once the alternator starts charging and the battery isolation solenoid closes.

sam-tip · 09-27-2010, 09:13 PM

I ran my house batteries down once to where I could not start the generator or run the furnace. There was a blizzard outside with temps down in the low twenties. I got worried. I left the refrigerator on battery and not gas. The frig ran the batteries down over night. I was able to started the main engine and then I was able to start the generator. A little scary at 4 in the morning and stranded in a hobby lobby parking lot on Christmas morning. With frig on gas both furnaces will run all night with out problems. That is with 6 month old house batteries.

skigramp · 09-27-2010, 10:22 PM

If you carry a set of battery jumper cables ... you can connect your two battery banks together for emergency starting even if the solenoid will not engage ...

georgetown350 · 09-29-2010, 06:06 PM

Quote:

If you carry a set of battery jumper cables ... you can connect your two battery banks together for emergency starting even if the solenoid will not engage ...

Good idea and one I might have to use as my battery boost switch doesn't seem to help. Do I have to use all 4 ends of the booster cables? or just one from positive to positive?

bachler · 09-30-2010, 03:05 PM

We have been avid snowmobilers =, untill 2 years ago, We have 2 chassis batteries and 3 coach batteries. 38 " winn, Ult adv., During the day we use the front furnace, at night we use the back one, The average fan draw is near 5/6 amps, devided between 3 batteries we have never had a problem. even at Yellow stone At 37 below zero, We watch tv for an hour or so in the evening to get the batteries full. then in the morning we start it to use the micro, and chg, the batteries. Been snowmobiling since 1974 Never had a problem. Make sure that the batteries are in good condition and not sulfated;

skigramp · 09-30-2010, 07:03 PM

georgetown ...

On my coach ... red to red .... the other side is connected to a common ground already