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tbsnrhurley's avatar
tbsnrhurley
Explorer
Jun 09, 2014

Propane consumption question

I have a Coleman 18HTT with a fairly decent sized refrig/freezer, I'm too lazy to go check the model at 11pm, but hopefully my picture will attach.


I am going to be dry camping for a week and am trying to determine if my frig can make it on my two 10# tanks.
Aside from chancing it, has anyone figured out how long their tanks will last.
This is my first time in this trailer for this particular camping trip. Previously I was in a pup with such a small frig I didn't bother, but went through a lot of ice.

I won't be using the furnace or stove much, but I might want the occasional hot water.

Thanks,
  • I think it more likely that you have two twenty pound tanks- ten pounders would be most unusual on even a small trailer. That's plenty of gas for a week in a trailer that size, even if you run the furnace, stove, and water heater at reasonably conservative levels.

    The real limiter is usually electric power...the fridge is one of several gas-fired things that can't operate without power for thermostat/controls. You don't say what your situation is there, but a single battery can run down in as little as three days, perhaps less if you use the furnace much.
  • LP consumption is easy to approximate.

    1. A pound of LP gas has approximately 22,000 BTU.

    2. The refrigerator in my camper -- looks like yours -- burns 1500 BTU/hour at maximum cold (highest heat). Note the data plate inside:



    3. 22,000 BTU/pound x 20 pounds/cylinder = 440,000 BTU/cylinder.

    4, 440,000 BTU/cylinder / 1500 BTU/hour = 293 hours/cylinder or about 12-1/2 days per cylinder at max cold -- per cylinder. Two of 'em will probably run a month.

    As noted above the refrigerator needs 12v DC to power the electronics.

    -- Chuck
  • Tvov's avatar
    Tvov
    Explorer II
    You should be fine with the propane. We've never even emptied one of our two 30lb tanks during a season of weekend camping.

    As Francesca posted, you need to be careful with your battery power. Look up threads on dry camping and/or boondocking for ideas and methods to save battery power. A "standard" deep cycle 12v battery can last a week dry camping with very careful use.

    When we've dry camped for a week, I've brought along a spare battery (usually the old battery from the TT that I replaced because it was over 5 years old). I make sure it is charged up before we leave home. I usually swap out the battery in the camper on the last night before we leave for home, that way we can "spoil" ourselves a bit and do things like turn the camper lights on, lol!
  • Keep in mind that it is VERY rare for your fridge to fun continuously. It will cool when it reaches the set point and turn off when it reaches it's cold set point which means in MOST cases it will run only about a few hours out of 24. My experience is that a 20 lb. bottle of LP gas when operating only the fridge would last a couple of months but will very due to ambient temperatures where you are camping.
  • Chuck_S wrote:
    LP consumption is easy to approximate.

    1. A pound of LP gas has approximately 22,000 BTU.

    2. The refrigerator in my camper -- looks like yours -- burns 1500 BTU/hour at maximum cold (highest heat). Note the data plate inside:



    3. 22,000 BTU/pound x 20 pounds/cylinder = 440,000 BTU/cylinder.

    4, 440,000 BTU/cylinder / 1500 BTU/hour = 293 hours/cylinder or about 12-1/2 days per cylinder at max cold -- per cylinder. Two of 'em will probably run a month.

    As noted above the refrigerator needs 12v DC to power the electronics.

    -- Chuck


    Chuck - I believe what's listed on your sticker is what the fridge consumes when it is running. So in reality, it will use much less than your total calculation, as the fridge won't be on all the time.
  • You need to be more concerned with your battery(ies). They are going to go WAY before your propane.
  • You are correct, sir!

    The placard lists the LP consumption at maximum cold so 12 days is probably a worst case scenario. But planning for worst cases keeps me out of trouble.

    The propane question normally occurs regarding use of the furnace in cold weather. Small RV furnace typically burns 19,000 BTU/hr which equates to just under 1 pound of fuel per hour of flame time. Wonder why it got go cold the 2d night with the furnace on most of the time! :) Ya only got about 20 hours of heat per cylinder so two is better. The kicker with the furnace is the motor pulls about 4 amps and the typical indifferently charged group 24 battery on the tongue only provides about 56 useful amp hours. Battery goes long before the propane. :)

    -- Chuck
  • to the OP, what are you doing to maintain your battery power?

    as you can see in the other posts, battery power is a WAY bigger issue than your propane supply.
  • I have a similar sized fridge and mine stays full on most of the time due to being in AZ, I can do about a week on a full tank of propane. Standard BBQ tank. Trailer has two on them which is normal.