Click here to Find a Contractor in your area.
In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Need to contact us? Visit

Propane tank ?

wrxz24wrxz24 Member Posts: 285
So I get a propane delivery today and they f ill the tank to 85%. I just checked the gauge the day before and it read 50%. They were able to put in 211 gallons in a 500 gallon tank. Question is, how accurate are the gauges? Thanks in advance


  • ZmanZman Member Posts: 3,476
    Not so accurate.

    That happens to me quite a bit. I think the gauge gets hung up.

    My propane company usually leaves the printout from the truck pump. As much as I love a good conspiracy, it is probably your gauge.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • wrxz24wrxz24 Member Posts: 285
    Conspiracy lol

    I must admit, that crossed my mind.
  • icesailoricesailor Member Posts: 7,265
    Propane Conspiricies:

    There's no conspiracy

    If you have a 500 gallon Propane tank, it is a horizontal hot dog tank. If they filled it to the tippy top, there would be no place for expansion and the gas to boil off the liquid in the tank. The reason they only fill it to 85% is to give the surface area to boil off the gas.

    I had a set-up and inspection today on a project I have been working on for a while to help straighten out. They fired off the LP gas on the dual fuel burner today. They have a 1,000 Gallon Hot Dog Tank and the racket coming out of that tank when the burner was on high fire and vaporizing 2.7 Million BTU's per hour was like no noise I have ever heard before.

    If the tank was overfilled, and there was not enough expansion area, if it was a sunny day, the liquid would expand and if there wasn't enough expansion room, the relief valve on the tank would pop.

    There's no conspiricy and they are doing their job correctly.
  • heatpro02920heatpro02920 Member Posts: 991
    No worries Im sure you got what you paid for..

    Ice is 100% correct, and I have heard that expansion noise a bunch of times, one of my commercial accounts is a plating company with 4 big Fultons and 6 commercial Rinnai tankless units.... I never heard everything fire at 100% at once, but I have heard them tanks on a moderate climate with a couple rinnais and a couple tube boilers pulling at once, plus the regulators making a racket... They only fill them to 65% at this property, I hate service calls there, regulators everywhere....
  • ZmanZman Member Posts: 3,476
    Original Question

    The original question was asking how you could take a 50% full tank (250 gallons) and add 211 gallons and end up with 85% instead of 92%. I believe the gauges just aren't that accurate.

    Thanks for the refresher on why you only fill to 85%. It's just a different subject.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • icesailoricesailor Member Posts: 7,265
    Not really/Relativity

    Not really. Tank gauges that have unusual shapes are relative indicators. Fuel oil and LPG gas delivery truck measuring devices are regulated devices measuring devices, just like the gasoline pumps at your friendly service stations. They have a tag from the local "Sealer Of Weights And Measurer" at your friendly city or town offices who are required to go out and measure things like that for accuracy.

    My work van which I drive is advertised as having a 36 gallon fuel tank. I have never run it out of gas but when it was as low as I dared to let it get, and the needle was as far into the "empty" as I was willing to let it go, the most I have ever been able to get into the tank was 33+ gallons. When I fill it up, they say not to fill more than the first click off. If I fill it up slowly, I get more in than if I use the fast fill. But I don't consider the gauge to be inaccurate. You're charged for what goes through the regulated meter.
  • ZmanZman Member Posts: 3,476

    That was my point. The gauge on the tank (and the one on your truck) are not that accurate, relatively.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • GordanGordan Member Posts: 891
    edited February 2013
    So the tank "fullness" gauge only measures...

    ...the depth of fluid in tank? If so, by the time the indicator is showing 25% you really only have 20%, and the gap gets rapidly worse after that.

    Assuming a cylindrical tank resting on its (rounded) side, but since the propane tanks are actually "shaped for your comfort" things would be slightly worse. I guess the point is: if you're down to 20% or so on the gauge, schedule a delivery. Soon.
  • icesailoricesailor Member Posts: 7,265

    The only gauge that is important is the one that the product goes through on the back of the truck and gives you a printout of how much was delivered.
This discussion has been closed.


It looks like you're new here. If you want to get involved, click one of these buttons!