How fast does propane run out? 2x Champion 2500w dual fuel

[swed02]

I understand "how much load" you put on it matters, but my primary concern is running the pair of AC units. In this scenario, does anyone have an understanding of how fast you blow through the stock propane tanks on the AS?

[jeffmc306]

Maybe someone with the same unit can chime in with real-world consumption but here’s what Champion says on their website: Up to 34 hours on a 20# propane tank. Your AS should have two 30# propane tanks.

Yes, lots of variables like temperature, altitude and load but let’s say “it can run a long time”.

We have a Champion 3400 dual-fuel and have used it sparingly so I don’t have much experience either.

[uncle_bob]

Hi

Running at idle with no load, they can run for quite a while. The gotcha is that your "run two A/C's" is far from no load. Specs for "half load" on a similar generator are in the 1.3 pounds per hour range. Running two would put you up around 2.6 pounds an hour. That puts you right at a day for "both tanks empty" if you have two 30 pound tanks and they are full.

Normal practice is to only fill a 30 pound tank to about 80% of the max. That puts you back to 24 pounds. You now need a refill after around 18 hours.

Bob

[Dennis C]

This concern is one of the reasons that I bought a gasoline powered generator. When we’re off the grid, we tend to run the furnace more that the air conditioning. Propane runs our fridge and our water heater. We use a gas grill and a portable gas fire pit. Most small mountain towns have a gas station. Not all of them have the ability to refill propane tanks.

[swed02]

Good insights. Thank you to "the collective," as this sort of answer doesn't seem to present itself easily on the general internet. Additional info as follows: our refrigerator uses elec. only. We do intend to use an exterior grill hooked up occasionally. Only the generators and water heater will be using the propane. I'm getting ready for our first big trip : 3 weeks. It begins in 1.5 weeks from today. I just want to be prepared.

[Dennis C]

I think you should consider something like Mopeka tank sensors so you know how much propane you’ve actually got in the tanks. Only run one tank at a time. When one tank is empty, switch to the other and then get a refill on the first tank. If you’re careful on your trip and you pay attention to propane refill stations then you should be able to stay ahead of it. There are quite a few campgrounds that offer propane refills, or you may see places on the road that can refill them for you.

[SHaley]

+1 on the Mopeka's you can figure out your burn rate with the A/C running.

[Mollysdad]

Try the old school method.
Take a glass of hot water, not boiling, and slowly pour it over the propane tank. In seconds you'll see and feel a line where the level of the liquid is in the tank.
The liquid absorbs the heat faster than the gas, so a line of condensation forms.

[drbrick]

We run the 3400 champ on LP - usually on eco mode. First thing we did was add a timer so we could monitor the usage. On a 20# LP tank we average 24-26 hours if we power the AS (never used the A/C so I don't even know if it works never really gets that hot in BC Canada where we Boondock )

[uncle_bob]

Hi

By far the most simple answer: Don't go off grid in areas you *need* to run the A/C. So far on our latest trip ( out since April ) we have hit a whopping max temp of 71 degrees on one day. Mostly the highs have been in the mid 50's so far. ( Yes, we do burn a bit of propane at night if we are off grid. The two 40 pound tanks started full and got refilled last week).

If cost is the issue, burning off 60 to 80 pounds of propane a day isn't at all cheap. The "typical" campground at $40 a night would be the lower cost alternative ....

Bob

[overlander63]

Originally Posted by uncle_bob

Normal practice is to only fill a 30 pound tank to about 80% of the max. That puts you back to 24 pounds. You now need a refill after around 18 hours.

Bob

30# IS 80% capacity for a 30# tank. Check the WC on the tank next time you're where you can do so, without a special trip.

[uncle_bob]

Originally Posted by overlander63

30# IS 80% capacity for a 30# tank. Check the WC on the tank next time you're where you can do so, without a special trip.

Hi

30# is 80% for a chassis mounted tank (like on the van). For a removable tank like on the trailer, most fill places only take it to 24 pounds. Same thing when you pick up a 20# tank outside the grocery store, it's got 16 pounds in it (at best).

Bob

[Wazbro]

Originally Posted by uncle_bob

Hi

30# is 80% for a chassis mounted tank (like on the van). For a removable tank like on the trailer, most fill places only take it to 24 pounds. Same thing when you pick up a 20# tank outside the grocery store, it's got 16 pounds in it (at best).

Bob

Nope, if they only give you 24 lbs in a 30# cylinder it is not filled to 80%, a 30# cylinder holds 37.5 pounds minus 20%.

Yes most of the exchange cylinders do only have 15 lbs, that is just to trick people into thinking it's the same price or cheaper to exchange then to get your cylinders refilled.

[Mark of SJC]

So, here's the "acid test" we sort of got forced into.

We have two AC's - (1) 15k and (1) 13.5, both with soft starts.

While I intended to make a connection to the LP port to run off the two tanks on the trailer...that didn't happen. So we ended up boon docking, in the AZ desert in 100F. Now our dual fuel Firman generator is bigger (3200 w) https://www.costco.com/firman-3200w-...100843922.html. We ran both AC's full tilt on those little BBQ-sized 5 gallon LP tank for about 8 hours....and they were running pretty much non-stop.

Note: Adding reflective insulation in the windows and insulated both skylights and the powered vent had a major effect! https://www.homedepot.com/p/Everbilt...LRFL/319738992

Hope this helps!

[SHaley]

If you look at 100% conversion from LP to Electricity 1watt hr is 3.41 BTU.
2000 watts is 6820 BTU/hr. 21,548 btu/lb for propane. so the run the gen for an hour at 2kw load then 0.316 lbs. It bet it wi be double that or 0.5 lb/hr at 2 kw load

[Ephraim]

Originally Posted by Wazbro

Nope, if they only give you 24 lbs in a 30# cylinder it is not filled to 80%, a 30# cylinder holds 37.5 pounds minus 20%.

Yes most of the exchange cylinders do only have 15 lbs, that is just to trick people into thinking it's the same price or cheaper to exchange then to get your cylinders refilled.

Our 2019 Classic has 40# tanks. If I run one dry, the LP company puts 6.5 gallons in it (pretty much determined by the safety float valve in the cylinder so it's the same where ever I fill it up). Propane weighs 4.11# per gallon @ 77*F. that means a 40# tank will take 26.71# of LP.

A 30# tank would be 25% less than that so probably closer to 20#

[urnmor]

I did not realize you could run the ac on propane for other then the furnace but then I never tried as I have Honda generators.

[10Smiles]

Originally Posted by Ephraim

Our 2019 Classic has 40# tanks. If I run one dry, the LP company puts 6.5 gallons in it (pretty much determined by the safety float valve in the cylinder so it's the same where ever I fill it up). Propane weighs 4.11# per gallon @ 77*F. that means a 40# tank will take 26.71# of LP.

A 30# tank would be 25% less than that so probably closer to 20#

My 2005 30' Classic also has 40# propane tanks. When I get a completely empty one filled the valve shuts off the fill at just over 9 gallons (let's say 9.3). So at 4.11 pounds/gallon, that is 38.2 pounds of propane. Pretty close to 40 pounds. Sorry for the thread highjack!!

[LNBright]

Originally Posted by urnmor

I did not realize you could run the ac on propane for other then the furnace but then I never tried as I have Honda generators.

The A/C is electric; they're using the propane to run their generators (ie, you can convert your Honda to run on propane).

[Ephraim]

Originally Posted by 10Smiles

My 2005 30' Classic also has 40# propane tanks. When I get a completely empty one filled the valve shuts off the fill at just over 9 gallons (let's say 9.3). So at 4.11 pounds/gallon, that is 38.2 pounds of propane. Pretty close to 40 pounds. Sorry for the thread highjack!!

Yep, you are right. I checked the last invoice and it was my 30# cylinders that I filled, not my 40#. So 26.7# of LPG it is.