LP Levels

[Hardhead417]

We are out on our first outing with our 2021 Isata 3. Since we only have 15 amp service available, we need to run the generator when we need the a/c. Our LP level indicated 30% so we went to fill the tank. It only took 11 gallons. Does anyone know if there is a calibration procedure for this reading. I can see a safety margin built in to the reading, but I think 30% when closer to 50% is a bit much.

[milkman55]

You have a 20.3 gal propane tank. Propane tanks are full at 80% of capacity. 20.3 x 80% is 16 gal of true capacity. You had used 70%, so it would take 11 gal to refuel to capacity.

You should have a second gauge on the tank itself in addition to your FireFly read out.

[milkman55]

On a completely unrelated note, your new generator has break in oil in the crankcase. Onan recommends you change that at 50 hrs. Also make sure and check the level before you run the generator especially for extended periods.

[Sandiegodoug]

So if the gauge on the tank reads 1/2, you actually only have 8 gallons left ? I never use the inside gauge, which is lights in my case.

[milkman55]

Originally Posted by Sandiegodoug

So if the gauge on the tank reads 1/2, you actually only have 8 gallons left ?

That’s correct. I never think of in gallons but how many days I can camp without filling. If you don’t use the generator or furnace it will last for weeks.

The generator uses anywhere from .5 to .7 gal per hour depending on load. You can burn through a tank pretty quick.

[dbaction]

Originally Posted by Hardhead417

We are out on our first outing with our 2021 Isata 3. Since we only have 15 amp service available, we need to run the generator when we need the a/c. Our LP level indicated 30% so we went to fill the tank. It only took 11 gallons. Does anyone know if there is a calibration procedure for this reading. I can see a safety margin built in to the reading, but I think 30% when closer to 50% is a bit much.

Here's a suggestion which I have done while my rv is in my driveway for mods or loading supplies...

Was using a heavy gage extension cord hooked to a 110v wall outlet.

Before operating one of the air conditioners (15000 BTU) on the 15 amp service I ran the generator and cooled down the inside with both ac's running. Then turned off the rear ac and all the other items in the rv, and the gen.
Then restarted the front ac which only ran on high for less than a minute before cycling down...checking the Precision plex screen it showed the ac consuming 11 amps after start up on high and then down to 2 amps while cycling.
Granted if you are camping and everyone else wants to watch TV or use the microwave this won't work. But should be ok for night time sleeping with only 1 ac running.

[Sandiegodoug]

Isata 3 has only one air conditioner.

[bclemens]

Originally Posted by milkman55

You have a 20.3 gal propane tank. Propane tanks are full at 80% of capacity. 20.3 x 80% is 16 gal of true capacity. You had used 70%, so it would take 11 gal to refuel to capacity.

You should have a second gauge on the tank itself in addition to your FireFly read out.

Spot on...

[Hardhead417]

Thanks for the responses. Never had a built in tank before. All makes sense now.

[Chuck_S]

You guys have 20 gallon propane cylinders? Just curious, these are big. Would be nice to have. Other than no way to fill other than dragging the whole rig to the refill point or having it come to you.

Propane tank capacity already accounts for the 80% fill level so a 20 gallon cylinder would hold 25 gallons if allowed to fill completely. Same for the standard 20 pound cylinders on your gas grill. Valves in the tank keep this from happening. The gas grill "tank exchanges" are a sham as they typically only have 16 pounds in them hoping you'll think that's standard and pay for a full tank. It ain't.

-- Chuck

[milkman55]

The cylinder capacity does not take into account the 80% fill level. The 20.3 gal as pictured below holds 16 gals per the manufacturer.

[bclemens]

Originally Posted by Chuck_S

Propane tank capacity already accounts for the 80% fill level so a 20 gallon cylinder would hold 25 gallons if allowed to fill completely.

-- Chuck

That is INCORRECT.

ALL tanks are stamped with their WC (Water capacity) not LP capacity. In the end it is "just a tank".

In fact, unlike other OEM's, I make sure that we note WC on our brochure. We noted that several OEM's would list their tank capacity, but we knew it was water capacity and they would not clarify. We used to list LP capacity, but when customers would think the other guys tank is bigger and did not understand. So by listing the tank size (not LP capacity) I am on level playing field and by noting "water capacity" I am not misleading anyone.