I have an 18 gallon tank that's filled now. We only use it for the water heater and we turn that off during the day. We heat water for 2 showers each morning and then turn it on once again a night to wash dishes. The water heater is gas only. How many days can I expect a tank of gas to last? I've never stayed this long before and have always just filled the tank before each trip.

Six weeks or more with your use. This is why I like double tanks. Use one, the other is full, switch over and start looking for a refill.

TNGW1500SE wrote:I have an 18 gallon tank that's filled now.Seriously? At 4.2 lbs per gallon that would be ~ 75 lbs ... you sure? Heck, I have two 20 lb tanks on my Coachmen, use propane freely for anything that may be needed, and may only refill one of those tanks during the course of the camping season. And you have 75 lbs?!! :h

....With the way you are using propane....you are going to be a lot older by the time you run out.

Only a rough guess, but I think at least a month, maybe more. But why not use the electric water heater if you are plugged in?

RoyF wrote:Only a rough guess, but I think at least a month, maybe more. But why not use the electric water heater if you are plugged in?It's gas only :(

How long will propane last? | Good Sam Community

Lwiddis
Explorer II
May 31, 2018
Six weeks or more with your use. This is why I like double tanks. Use one, the other is full, switch over and start looking for a refill.
SoundGuy
Explorer
May 31, 2018
TNGW1500SE wrote:
I have an 18 gallon tank that's filled now.

Seriously? At 4.2 lbs per gallon that would be ~ 75 lbs ... you sure? Heck, I have two 20 lb tanks on my Coachmen, use propane freely for anything that may be needed, and may only refill one of those tanks during the course of the camping season. And you have 75 lbs?!! :h
downtheroad
Explorer
May 31, 2018
....With the way you are using propane....you are going to be a lot older by the time you run out.
RoyF
Explorer
May 31, 2018
Only a rough guess, but I think at least a month, maybe more. But why not use the electric water heater if you are plugged in?
TNGW1500SE
Explorer
May 31, 2018
RoyF wrote:
Only a rough guess, but I think at least a month, maybe more. But why not use the electric water heater if you are plugged in?

It's gas only :(
Old-Biscuit
Explorer III
May 31, 2018
Your Class A propane tank with 18 gallons will last this whole camping season

Water heater at most uses a 12,000btu/hr burner which you are only burning propane for 20 minutes 3X a day........roughly 12,000btu
Gallon of propane has 91,600btu....would take you 7 days to use 1 gallon (if only using water heater)

You have many many days of propane use
TNGW1500SE
Explorer
May 31, 2018
SoundGuy wrote:
TNGW1500SE wrote:
I have an 18 gallon tank that's filled now.

Seriously? At 4.2 lbs per gallon that would be ~ 75 lbs ... you sure? Heck, I have two 20 lb tanks on my Coachmen, use propane freely for anything that may be needed, and may only refill one of those tanks during the course of the camping season. And you have 75 lbs?!! :h

The tank says "18 gal" right on the label.
the_bear_II
Explorer
May 31, 2018
We leave our water heater and refrigerator on propane when boondocking 24/7 and our propane lasts for several weeks. Two standard sized tanks.
SoundGuy
Explorer
May 31, 2018
TNGW1500SE wrote:
I have an 18 gallon tank that's filled now.

SoundGuy wrote:
Seriously? At 4.2 lbs per gallon that would be ~ 75 lbs ... you sure?

TNGW1500SE wrote:
The tank says "18 gal" right on the label.

Then why worry about it? ... that's enough to last most people a couple of seasons!
time2roll
Nomad
May 31, 2018
Yes an 18 gallon RV tank should last a long time with just water heater and maybe some use of the stove. A trailer with two propane cylinders carries about 10 to 15 gallons and lasts a long time also.

You will need to watch propane level much closer if using the propane furnace to stay warm in sub-freezing temperatures or using a propane generator to run the air conditioner 24/7.