Fridge and propane

A Norcold N641 refrigerator/freezer model will run approximately 2 1/2 weeks (with stove cooking as well) on a 30lb tank. Probably the full 3 weeks if it's just the refrigerator. This is in 75-90 degree temps.

Thanks for the numbers Soundguy.

The OP has still not replied to tell us what size and what type of fridge, BOTH of which are critical to determining just how long any gas absorption fridge might run in the gas mode. For example, one of the most commonly found gas absorption DSI fridges found in travel trailers these days is the Dometic DM2652 which is rated to consume 1501.28 BTU/hr. IF the flame actually burned constantly then in 24 hrs it would consume ~ 36,000 BTU/24 hrs and since a 20 lb tank of propane is worth about 420,000 BTU this fridge in theory would run for just 11.6 days. HOWEVER, the flame in a DSI fridge does NOT run constantly but cycles on/off as necessary to maintain proper interior temps, in which case the number of hours / days this fridge would continue to run depends on a number of variables, from exterior temperature, whether the trailer in which it's mounted is sitting in direct sun or is shaded, to how often the doors are opened, whether it's equipped with additional cooling fans, etc, ALL of which will determine how often the fridge flame cycles on/off and therefore how much gas it will consume.

In comparison, another popular fridge at the other end of the spectrum is the Norcold 323 manual light 3-way fridge that's often installed in popup trailers. Since I owned one I know it consumes ~ 625 BTU/hr but since this is not a DSI fridge, has no electronics, and the flame runs 24/7 it would require an average 15,000 BTU in 24 hrs, regardless of exterior influences. Since a 20 lb tank is worth ~ 420,000 BTU that means this fridge would run continuously for ~ 28 days even though it's flame is burning constantly. Since it has no electronics to vary it's consumption that rate will be fixed regardless of exterior temps, etc - rather it's performance will falter in extremely high temperatures.

Bottom line - unless OP specifies the type & size of fridge there's just no way for anyone to even remotely estimate how long a fridge may run on any given size of propane tank. ;)

ScottG wrote:
Been asked many times. It uses so little that I don't think anyone has ever come up with a definitive answer.

Agreed.

Hi,

If boondocking without way to charge the battery bank you will run out of "juice" before you run out of propane.

Maybe this will give you an idea. I just got 22 days on a 20lbs tank towing my camper from Alabama to Glacier National Park and back. I hit a few other places of interest on the way out and back as well. Dry camped for 5 days, the rest I had shore power. Hot water heater was ran daily with propane, and furnace was ran for 2 nights. Low temps were high 30's low 40's and highs were in the upper 50's.

Last I read was 4 to 6 weeks on a 30 lb cylinder.

Variables like ambient temp. how often you open the door, size of fridge are only questions you can answer. The trick is it takes the same # of btus to operate an absorption fridge on elec. as on propane.

Given that a KW of elec. is 5160 btus ,at a cost of ? in your location, propane is ? / 5160 btus?
Weigh your costs for each.

Like was mentioned above, very slowly. I have been on the same tank since the beginning of spring. Only use the propane on the refrigerator when going and coming back, last trip before this one was about 8 hours on it going and coming back, very little was used.

Not sure of my capacity, but during a visit to a local RV dealer and repair shop, they did not turn off the refrig like I told them to do. 1-hour repair event turned into a week before I picked it up and told them to forget about the repair, and my propane tank was empty. They did refill it for me, but I haven't gone back to them for service ever again. So in our case, about a week.