20 lbs to 20 lbs Refill/Transfer

PopUpSteve

Administrator
Staff member
Gold Supporting Member
Dec 22, 2002
21,124
Southeastern PA
Wondering if it’s feasible to refill/transfer propane to an empty 20 lbs tank from a full 20 lbs tank?

Asking for a friend.
 

jfilz

Member
May 11, 2012
29
Yes with proper fitting and equipment it is possible but why? Cost for fitting etc...cheaper to just fill tank at Costco!
Wondering if it’s feasible to refill/transfer propane to an empty 20 lbs tank from a full 20 lbs tank?

Asking for a friend.
e
 

SteveP

Super Active Member
May 21, 2015
2,606
Do your expensive tanks require recertification. There is a process called "drift fill" which is pretty much the same as filling empty 1 pound cans. Both cyls are connected by a hose, the full cyl is placed upside down and higher than the empty. The liquid will slowly settle into the empty cyl. If you set the empty on a scale you can tell when the process is complete. When the transfer is complete turn off the valve on the receiving cyl. Turn the sending cyl right side up and give it a minute to let any liquid in the hose to drain back into the cyl. You can speed it up by opening the vent on the empty cyl but I'd want a 1/4 turn ball valve in the hose to do that. Wear gloves and eye protection.
 
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Sjm9911

Super Active Member
May 31, 2018
12,224
Nj
Dont some of the vents on the 20 lbs have breakable disks? Once open they stay open untill replaced?
 

Sjm9911

Super Active Member
May 31, 2018
12,224
Nj
What other vent is there? The guy at the propane place ( they do only refills on gasses and fire equipment) told me some of the overflow valves are breakable. Just a plastic disk inside. And sometimes when they blow they break. Backstory was a propane tank with a relief valve that would not close. I was trying to get information as to how to shut it down without having to sit and wait untill the 20 lb tank emptied. Cooling it didnt work, and it wasnt really hot anyway.
 

tfischer

A bad day camping beats a good day at the office
Not sure what the reasoning is behind this. If it's tank certification... that's the one time I use tank exchange. For a few bucks more than the refill price, I get a recertified cylinder that can then be refiled again once emptied.

There are reasons for the tank recertification laws and I wouldn't push a tank much past the deadline personally.
 

Sjm9911

Super Active Member
May 31, 2018
12,224
Nj

bupkis

Howdy!
Mar 3, 2006
7,934
N. TX
to the atmosphere

during filling by volume it is used to vent, when liquid begins to vent it indicates 80% full.
 

SteveP

Super Active Member
May 21, 2015
2,606
It would be easier, and safer, to place an extend a stay connector between the empty tank and the pigtail to the regulator. Connect the spare tank to either of the outlets on the connector and refill when you're back in civilizatiion. To use the 1" connector, which I would prefer, you would need a 20# to 1# adaptor on the spare tank and a matching hose.
 
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Lug_Nut

Active Member
May 29, 2016
283
Mt. Wachusett area, MA
Wondering if it’s feasible to refill/transfer propane to an empty 20 lbs tank from a full 20 lbs tank?

Asking for a friend.
At absolute best you'd your friend, would end up with two 20 lb tanks with 10 lb propane each.
The pressure in the 'full' tank would push liquid (tank situated with outlet valve low) or gas (tank in upright position) into the lower pressure, 'empty' tank only until the pressure was equal. Then the flow/transfer stops. You'd Your friend would also lose the small amount of fuel (gas or liquid) remaining in the interconnect hose when that was removed.
Is your (friend's) tongue tank mount that time consuming to justify disconnecting (but not removing / exchanging) the empty tank to gain a partial fill?
 

swe13

Member
Mar 18, 2018
12
At absolute best you'd your friend, would end up with two 20 lb tanks with 10 lb propane each.
The pressure in the 'full' tank would push liquid (tank situated with outlet valve low) or gas (tank in upright position) into the lower pressure, 'empty' tank only until the pressure was equal. Then the flow/transfer stops. You'd Your friend would also lose the small amount of fuel (gas or liquid) remaining in the interconnect hose when that was removed.
Is your (friend's) tongue tank mount that time consuming to justify disconnecting (but not removing / exchanging) the empty tank to gain a partial fill?
His friend could wrap the tank he is filling in ice and heat the other tank, by sunlight, hot water or heating pad (no not a torch). In my friend's experience, he could probably get maybe max of 60% in the empty tank (probably closer to 55% in reality) Not sure if its worth it though. Not usually a quick process (probably quicker to switch the tanks after all said and done) and there are the possibility of bad things happening. If parked and not traveling, an extension hose to the new tank is probably the easiest.
 




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