How Long Will The Propane Last When I Run My RV Furnace?

by Meme

How Long Your Propane Will Last When You Run Your RV's Furnace

How Long Your Propane Will Last When You Run Your RV's Furnace

Our 1997 5th wheel is central air and ducted, and we just purchased it. The furnace comes on when the thermostat control selects the furnace mode. The owner we purchased from said he only ran the furnace to get the chill off.

Others have told us to buy a Portable Electric Heater because the furnace would burn up the gas quickly. Is this true? About how long would a 40lb tank last if we were running the furnace during cold weather?

ANSWER: Hi Meme, I am afraid that you are not going to like my answer. My answer is, "I Dunno." There are too many variables for me to give you a conclusive answer. The answer depends on several factors; how well your 5th wheel is insulated, the outside temperature, what temperature you have the thermostat set to, whether you need to run it both day and night, whether your RV is equipped with more than 1 furnace, etc.

The best way of finding out is to fill up your propane tank and run the furnace until you run out of Propane, and then you will know the answer for sure.

If, after you do this experiment, you decide that you need an alternate or supplemental way of heating your RV, you can choose to use an Portable Electric Heater. A lot of RVers safely use portable electric heaters in their RVs. The keyword here is "safely use." Here are a few rules to keep in mind when using a portable electric heater in your RV.

Over 1,500,000 successful roadside rescues—Good Sam RV Emergency Road Service

1. Use only heaters that have been tested
and approved by a recognized independent testing lab.

2. Buy only heaters with automatic shut-off switches that activate when the heater is tipped over.

3. Keep the heater at least 3 feet away from any flammable materials.

4. Do not overload the 120-volt electrical circuits on your RV.

5. Do not use an electric heater with a damaged power cord.

6. Do not use an extension cord with an electric heater.

7. If you travel with pets, make sure that the heater is secured so that the pets cannot knock it over. SPECIAL NOTE FOR PET OWNERS: If you think that your pet may be capable of knocking over a standard electric heater you may want to purchase a Portable Oil Filled Radiator Heater as they do not get hot enough to start a fire if accidentally tipped over by your pet and they also do not get hot enough to accidentally burn your pet.

If not used properly, any heater being used in an RV can cause serious injury or death.

Final suggestion: If you want to keep using your propane for heating, but you are worried on how often you will have get the propane tank filled up, you can install a Propane Adapter Kit to your RV's existing propane system. The Propane Adapter Kit will allow you to add an additional larger stand-alone Propane tank to your RV.

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As you can see from the video a Propane Adapter Kit will also allow you to hook up your portable propane grill to to your RV's propane tank.

I hope that this information has been helpful to you.

Comments for How Long Will The Propane Last When I Run My RV Furnace?

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propane usage
by: George Charles Jr

I used two oil-filled electric radiators in my previous 33 foot camper for 5 years and was very warm in 0 degree weather.
My newer 37 foot 5th wheel camper has me very cold in 35 degree and colder weather even though I have the same two heaters on. On a suggestion, I tried infrared heaters, which were much warmer, but it was 21 last night and 43 inside. I want to use my propane heat only for a backup.

Propane lasts not long
by: Anonymous

One 30lbs cylinder last approx 1wk, using it for heat and cooking.So yes a small space heater is a plus.

Get a 500 pound tank if you can
by: Anonymous

I’m a full time permanent camper. 32 foot pull behind with a leaky wall. I had the propane company out a 500 gallon tank in my yard and it has lasted two years and I’m just now at 20 percent. If you travel The small tanks suck but if your allowed to have a big tank it’s worth it. I also asked the company if I moved how fast could they come get the tank and they said as soon as I tell them I need it moved they’d come get it.

How long will my furnace run on my propane tanks.
by: Chuck Marik

One pound of propane has 21,000 BTU of energy.
Therefore if your furnace uses 31,000 btu per hour
And you two 30 pound bottles you have 1,260,000
BTU of energy, therefore your 31,000 BTU furnace
Would run 40.64 Hours continuous !!! So if it runs 30 minute pre hr it will run out in 80 hrs or 3 and a third of a day.... So with these numbers yall will be able to figure it out !!

Electric/Gas Hybrid Furnace
by: Larry McGaugh

RV Comfort Systems, has successfully engineered an electrical heating option, an add-on assembly to any RV propane furnace, so today's RVer can simply choose propane or electricity to heat the interior of the coach. Called the CheapHeat™ System, this unit is mounted directly downstream of the existing gas furnace and employs tungsten heating coils powered by 120 or 240-volts AC to provide the heat. The 12-volt fan motor on the furnace then pushes the heated air throughout the distribution ducting in the coach. It can be configured into three different wattage ratings, 1,800, 3,750 and 5,000 watts, depending on the shoreline cord limitations.

The only connection between the CheapHeat™ and the existing propane furnace is a simple wiretap on the fan motor conductor. According to CSA America (the RV Furnace certification group) it DOES NOT effect the ANSI certification of the gas furnace.
More info at or Call 425-408-3140

Don't forget to factor in cooking and hot water!
by: Anonymous

We live in NW WA so it is not only chilly at night, but damp.

Have a 34' Dutchman 5th Wheel with 4 slides and tall ceilings.

Propane runs not just our heat, but hot water and oven/stove.

My husband loves it warm to hot, I prefer cool to warm and since our bedroom is in the front upper part of the RV, it gets warm quickly.

I have seen many full-timers place the metallic emergency blankets and windshield covers in their windows during winter, but to me, that is ugly...

We have fan pillows that go into our ceiling fans (purchased at Walmart cheaper than anywhere else),
I purchased thermal draperies and cut them to fit, placed them on tension rods and they fit perfectly inside our window valances and keep the chill out. I also use one over the door area to keep the chill out.

We also use a dehumidifier and run our ceiling fan in reverse mode.

Since we are full-timers and in a permanent spot, this summer we are adding wooden skirting backed in insulating material to prevent wind from coming under the RV.

We have a heated fireplace under our TV and we use LED heaters only when necessary.

We went through 2 of the smaller tanks weekly last year, but got Propane for a deal.

This year we are thinking of buying a larger tank and having our local propane company fill it monthly.

For all the showers (2 per day), cooking (daily baking and cooking) and heat we do, we truly do not burn through that much!

Electric heaters
by: Anonymous

My propane furnace knocks off the chill pretty quickly. Mine also came with a built in electric fireplace under the tv for not so chilly days.

Propane usage
by: Anonymous

A 40 Lb tank has 180000 BTU worth of fuel. If you have a 10000 BTU furnace, you will have 18 hours of use per tank. If your furnace is 20000BTU you have 9 hours of use per tank. Hope this helps!

electric vs liquid petroleum (LP)
by: full timer in carson valley

Something to keep in mind is if you have to pay for electric then propane will ALWAYS be cheaper to heat with but if you are staying nightly and get electric free then use as much electric heat (i.e. space heater fans) as possible because free beats just the effort of exchanging or filling LP tanks let alone the cost.

We use ceiling unit to put out air slightly warmer and space heaters for main heat when visiting an area (camping) when having electric hookups but still like the furnace for quick warm up first thing in morning. But for where we live full time we never use space heater because it costs too much.

Here in Carson Valley with 2003 34' fifth wheel in December/January with many nights between 5-20 degrees we go through about 80 gallons of Liquified Petroleum Gas (LPG/propane) every month but that includes our continuous heat water heater (i.e. on demand water heater) and I like long hot showers every morning for my back. Others here use around 60-70 gallons if no space heaters and normal rv water heater. Its amazing how many people will drive electric bill up $100 to save $50 on propane bill. lol

Stick with Space Heaters!!! ..........
by: Anonymous

We have a 2013 Keystone Cougar 36' fifth wheel (333mxs) and a 30 LP tank, full w/furnace set @ 70 degrees (it was 45 outside!) lasted THREE DAYS!!

At 30 bucks a fillup, that'd be THREE HUNDRED+DOLLARS A MONTH!!!! We now have three new Holmes rotating 1500 watt quartz space heaters which keep it toasty warm!!!

Warm Oil Heaters
by: Anonymous

We have two smaller 300 watt warm oil heaters with tip shutoff. We found bigger ones blow our breakers too easily.

We like the oil ones because they are relatively pet safe since they never get really hot and they don't suck in and burn dust and pet hair and smoke and fume the way heater element type floor models with fans do. We have one at each end of the trailer and set the thermostat for 70 daytime and 65 nighttime. The furnace almost never goes on during the day. The little heaters are sufficient.

The furnace will run will run during the night. We have found we only need about one of the smaller propane tanks/month during weather that goes below freezing at night but above freezing during the day which can happen in our winter resort. Watch that electric bill though! If you are on metered power propane might be cheaper than the meter. At one place we stayed at they charged such a high fee for the metered power we were paying $70/week for electricity half if it heat. (We didn't go back there.)

Propane Usage in 5th wheel RV
by: Texasgal4sure

I have a 33 ft Alfa 5th wheel with 3 kingsize slideouts and with 9 ft ceilings, and it is a well insulated seasonal RV. I reside in it full time and it has withstood over 70 m.p.h. wind with the slideouts out.

We have very cold weather with snow in the winter time. I have 2 40 lb propane containers for a backup since we have propane at the RV Resort I reside in. I rented a 100 gal propane tank that I fill between 3-4 weeks if I run the furnace day and night. I keep my thermostat set on 74 degrees at all time.

I do have 14 large windows so that is why it takes a lot of propane in the winter time, but I love seeing outside and enjoy the sunlight in the summer time. After the winter months in March, I don't fill the large propane tank again until October. My hot water heater is all that is used on propane during the spring and summer months. I use hot water for my washer, shower, and 2 sinks.

I went to Lowe's and purchased a tower electric oscillating heater that works really good. I used the 2 small propane containers when I first bought my RV and they only lasted 2 days each. I rented a small tall round slender cylinder and it lasted 1 week so then I rented the large container that lasts me 3-4 weeks.

I am very cold nature so I probably spend more for propane than the normal person. It is controlled by my thermostat. I have a 3 in 1 furnace unit in my underneath compartment of my RV. The thermostat controls all 3 units. I have air conditioning/propane heat/electric heat.

I am elderly and live very comfortable with my 2 dogs in my 5th wheel. There are several of us living full time on permanent basis at the RV Resort. Awesome life for all of us!!

LP Gas and Staying Warm
by: Lance

The great RV question - how much gas, and when I want to get warm, how much then?

The answer varies, as many have said, from RV to RV, and your setup, your desired warmth level, your furnace efficiency, etc.

I worked with specialty trailers for years, installing toy hauler LQ's etc., and a general rule for 32-degrees that we used was 'tank size / trailer length-ft * week' a general rule of thumb for a 65-degree interior and balanced equip. This would mean that a 20-ft trailer, with a 20-lb cylinder would last a week (assuming minimal cooking and showers, good 'closed-door' management, and good seals. Overall, this number has generally worked for my rv excursions. I have a 25-ft fifth wheel, got two 40's up in the riser basement (one tied in to the splitter manifold with the 40# in the LP cubby), and with 80-lbs on a balanced system, I can get about 67-degrees interior when around 30-32 outside temp, and hold it about a month before refills...(still having a full 'spare' and maybe a couple of gallons in that last manifolded tank). I cook when I want, have hot showers when I want, and as even most full-hook-ups are now strongly adhering to the 20kw per night before is really good to heat your own via gas, than to pay them for more kw's on the old shore cord.

Just consider what a dear friend told me...we spend 10, 20, $40k and more for our trailers. Sometimes even more expensive toys inside. We are on vacation, and want comfort and relaxation. We will burn $200 - $400 of gas or diesel to get there and get back...why, exactly, are you going to skimp on $20 in Propane, to ruin it all? If you can, upsize your tanks (I always go straight to 40' much more economical, if they will fit). If you can, upsize and add a spare. Add a manifold if you can (or just keep them as 'back-ups'). Install proper constraints for the tanks. Some of the best money you will spend is $100-$200 for bigger tanks / spare tanks. Fill them, load them, and forget them. Check them after each outing...and remember...even right now, at $3.45 a gallon, you can fill two 40's for around $52. That's cheap warmth!

Good luck, and safe travels.

Lp usage amounts in colder weather
by: Anonymous

I have a 30 foot 1984 Winnebago. It has a 20 gallon Lp tank. In low temps of the night reaching down to 22 degrees F., my Lp tank ran 4 nights and 5 days. Temps during the day was 40-46 F. and used Lp only for the furnace. Did not use Lp for refrigerator or water heater during this time period. There was about 1-2 gallons left after these days.

One more thing....
by: Traveling On The Outskirts

Do NOT just rely on your gas heater - always have a backup!

Our heater worked perfectly at home. As soon as we got in the mountains, 2 foot of snow hit the ground and the heater worked until about 2am.

Later we had time to fix it, but at 2AM when you wake up shivering, you'll wish you had that backup plan instead of fumbling around in the snow!

BTW the nearest walmart was 45 minutes away - so we had to just bundle up and wait for the morning! That was one chilly night!

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