Propane tank question

[WDH]

Those oil arguments are tiring long and drawn out, so the guests end up drinking a lot of beer  :D.

[Hilltop366]

There are so many replies about the propane tank you would think it was a grease gun. ;D

[Gary_C]

There are so many replies about the propane tank you would think it was a grease gun. ;D

Thank you!  We like to leave no stone unturned.   

[Al_Smith]

It's a slight break from the oil wars . ;D

Interesting,they pinch you a little bit on those bottle swaps .No wonder they don't belly ache about old bottles .

[Jim_Rogers]

Well, I never got to test any of the solutions you guys suggested to me, as my tank went dry today while trying to warm up the backhoe engine enough to start.

So, I went to my local hardware store that sells propane, the place where I normally get it. And got it filled up.

The nice girl clerk told me that the tank weighs 20 lbs empty and 40 lbs full. And they charged me $20.
They had a sign on the gate that said $4 a gallon if buying by the gallon.

Jim Rogers

[Thehardway]

Jim,

Your lucky, you now have a known full tank to use for reference.  Best way to keep from running dry is to find an old spring style hanging scale or fish scale. You could even make your own with a screen door spring, 2 hooks and a peice of pipe. Put your full tank on it before you use any and make a reference mark at the point the bottom of the spring hangs down. Label it full. Put an empty tank on the same spring and mark that point as empty.  Now you have your own quick reference propane gauge that will work fairly accurately, regardless of outside temps. 

My propane grill has a fancier version of this setup but same general idea.

A lever/counterweight scale would work too.  Just need a full tank to establish reference weight.  You get the concept, don't need to measure real weight in pounds.

[Al_Smith]

 :D Jims' just going to get off that moldy money and buy a couple more tanks is all .Now long as I've lived I've never seen a Brinks truck in a funeral procession .

[beenthere]

I just keep a full tank in reserve. Then try to remember to have the empty on filled before the good one is empty. ;) ;)

[Jim_Rogers]

After my wife leaves for NC for Christmas to visit her grandchildren, I'll go out onto the front porch and get the tank out of the grill that belongs to her daughter's boyfriend. They'll never know it's gone until May.....

Jim Rogers 8)

[Al_Smith]

Well you might care to get it full before May else you might get a raw hamburger .That would be bad ,yuck.

[Gary_C]

Sounds like a good plan Jim.

If they say anything, just tell them the gas was going to go bad setting over the winter anyway. You just saved them from cleaning out a mess in the spring.   8)

[jwilly3879]

We do propane tank exchanges at my wife's convenience store and when somebody slips in an old tank or one without the triangular valve we pay for a new tank. The employees are mostly trained now but it got expensive for awhile. So if you are looking to get rid of your old tank for a newer style please don't do it at your local Mom and Pop tank exchange, they are paying for the tank you got.

[Rockn H]

I still like being able to just glance at a gauge to see how much is left in the tank, and not having to worry about checking the weight.  Just screw the gauge on your tank and then your hose onto the gauge.
Here's a pic of a gauge at Lowes for about $12.   You can put together a more accurate gauge similar to this one using fittings from any hardware store and an old acetylene gauge.

[Jim_Rogers]

I'll look at Lowes and see if I can find one.

Thanks for the tip.

Jim Rogers

[John Mc]

Jim,

Your lucky, you now have a known full tank to use for reference.  Best way to keep from running dry is to find an old spring style hanging scale or fish scale. You could even make your own with a screen door spring, 2 hooks and a peice of pipe. Put your full tank on it before you use any and make a reference mark at the point the bottom of the spring hangs down. Label it full. Put an empty tank on the same spring and mark that point as empty.  Now you have your own quick reference propane gauge that will work fairly accurately, regardless of outside temps. 

My propane grill has a fancier version of this setup but same general idea.

A lever/counterweight scale would work too.  Just need a full tank to establish reference weight.  You get the concept, don't need to measure real weight in pounds.

You do need to keep in mind that all empty tanks are not the same weight. Still, most are within a pound or so of each other, so that mark on a spring scale will at least give you a decent reference

I've used several different fill stations over the last few years.  None of them are using their scales any more.  Since the OPD valves became standard, most are just filling until the relief valve pops.  Some charge "by the fill", a price that assumes you are empty (whether you actually are or not).  Some charge by the gallon.  Some who charge by the fill will stop at 4 gallons (or some other set number), whether it's full or not.

[T Red]

I still like being able to just glance at a gauge to see how much is left in the tank, and not having to worry about checking the weight.  Just screw the gauge on your tank and then your hose onto the gauge.
Here's a pic of a gauge at Lowes for about $12.   You can put together a more accurate gauge similar to this one using fittings from any hardware store and an old acetylene gauge.

This gauge does not work as one would expect.  It is measuring the gas pressure in the tank not the liquid level.  As long as you have some liquid in the tank the gauge will say it is full.  The pressure of the gas in the tank varys a lot with the temperature of the tank.  So if it is really cold the pressure will be low and so would the needle.  Hotter the higher the pressure. So even if you only have a few ounces of fluid left in the tank you would have full gas pressure(depending on temperature).  As you use that last bit of propane the liquid turns to a gas and you are left with only propane gas.  From there your gauge will start dropping quickly and saying you are out, of course by then you are out.

[beenthere]

T Red
Good reply.
What I've heard too... the gauge just confirms why the burner just stopped producing a flame or won't light. Doesn't give much pre-warning information.

Best, IMO, to just spend the money for an extra spare tank.

Nothing worse than a partially cooked grill full of steaks or burgers or brats, and the flame goes out with all those hungry people standing around drinking one more round while you buzz off to the nearest gas depot (if one is open that services tanks). Spend almost as much running the vehicle to town as the propane needed.

[Rockn H]

T Red,  yes and no.  I've used a 20lb propane tank on my cutting torch for years and that's where I got the ideal for using the same type gauge for the camp back in the day.  The gauge will start out above 150 lbs pressure and slowly drop as you use the propane.  It doesn't just stay at the top and then suddenly start dropping.   Yes, temperature does play a role in how the gauge is going to read, but you still get a good ideal as to how much you have left.  I'm not saying it's as accurate as weight, because temperature doesn't affect weight.  I'm just saying for me, it's quicker to have a gauge on the bottle and just glance at it.   I'll add that I don't know how well the gauge I pictured works, I've always used an acetylene pressure gauge off of a regulator that just reads up to about 400lbs.  I'd think they'd work the same though. 

[Al_Smith]

Propane in leau of actylene is a less expensive option .Some like it,I don't .

Long winded conversation about propane tanks and  remembered I have two more I had forgotten about .One on a 6 panal catalitic heater ,Ember Glow  I have in the garage .Another on a lead pot I have to "boot leg " to get filled .Top discharge valve non safety type .

C'mon Jim get some more tanks ,I have 10 . ;D

[Mooseherder]

I bought a tank for the Pizza Oven at a grilling store.
They also do refills there.  The tank has this type gauge on it.
I haven't had to refill yet so I don't know if they're accurate.
When I move the tank around the gauge fluctuates as the pressure moves inside the tank.



 

[Gary_C]

T Red,  yes and no.  I've used a 20lb propane tank on my cutting torch for years and that's where I got the ideal for using the same type gauge for the camp back in the day.  The gauge will start out above 150 lbs pressure and slowly drop as you use the propane.  It doesn't just stay at the top and then suddenly start dropping.   Yes, temperature does play a role in how the gauge is going to read, but you still get a good ideal as to how much you have left. 

The reason the pressure drops as you draw propane from the tank is because of the cooling effect of evaporating liquid propane inside the tank as you remove propane gas. What is really happening is you are lowering the temperature of the tank and the vapor pressure of propane is lower at lower temperatures. So when you interrupt your draw of gas, the temperature of the tank and contents will go back up to ambient and the pressure will go back up to where it was when you started.

So as T Red said, there is a sharp drop in pressure the instant the last drop of liquid in the tank disappears. So those pressure gauges are really just indicators to confirm they are empty.

[trapper]

Had a bottle filled at local propane company and weighed it.  just exchanged a bottle at menards and weighed it.  7 pounds lighter than the one filled locally.  Reading this thread caused me to weigh the bottles. Another value of the FF family. 

[gspren]

Had a bottle filled at local propane company and weighed it.  just exchanged a bottle at menards and weighed it.  7 pounds lighter than the one filled locally.  Reading this thread caused me to weigh the bottles. Another value of the FF family.

My one nephew worked for one of the tank exchanging outfits delivering bottles a few years back so he lifted bunches of them. At first they held 20LBs, the next year 17LBs and now 15LBs. The paper tag listed the weight so it's legal but deceiving, who reads the paper tag. >:(

[Al_Smith]

I think it's pretty much a known fact you don't get a full bottle .They get by with it it because it's conveniant .In my case it's a way to get rid of my old bottles of which I have one left .I think right after the holidays I'll do that very thing.

[John Mc]

Had a bottle filled at local propane company and weighed it.  just exchanged a bottle at menards and weighed it.  7 pounds lighter than the one filled locally.  Reading this thread caused me to weigh the bottles. Another value of the FF family.

Remember there can be some significant difference in the empties.

Some (Most? All?) of the tank exchange businesses are not providing full tanks, however, I've never seen one marked s containing less than 15 pounds.