Leaking propane tank.

[swimmer_spe]

I had a full 20lb propane tank sitting in my garage. I noticed a smell of propane and there was an odd noise coming from it. Turns out, the relief valve was letting propane out.

I am wondering if due to the heat we now have if it wasn't overfilled.

Do those relief valves reseat, or do they keep relieving till empty?

It is sitting outside, far from any source of flame or ignition.

[Joe417]

I've experienced the relief valve venting on 3 occasions over the years and they didn't leak a little. They popped wide open, putting out a cloud of gas, vented for a few seconds and then closed back.

Scared the heck out of me for just a second. Never had one that leaked a little.

It may be a different method of venting I haven't seen.

[time2roll]

http://www.propane101.com/propanetankleak.htm

Relief Valve Actuating
On hot days when the sun is high overhead and a propane delivery has recently been made, the safety relief valve may open slightly allowing excess pressure to vent. If the relief valve is opened, the protective cap will be removed from the top of the valve from the pressure buildup, as pictured to the left. DO NOT LOOK INTO THE RELIEF VALVE OR TAP IT WITH ANYTHING. Doing so may cause the relief valve to open all the way. The relief valve is doing what it was designed to do and on hot, sunny days, propane tanks are subject to excess pressure due to expanding liquid within the tank. One way to remedy the situation is to cool the tank down by spraying water from a garden hose on the surface of the tank. This will generally cause the relief valve to close.


I believe the article primarily is about large home propane tanks.

And I will add that these propane cylinders should not be stored indoors. My new cylinder sits out on the patio until I empty and dispose of my expired one.

[agesilaus]

Probably the best thing to do is let it vent completely and then take it to one of those local places that exchanges tanks. Exchange it for a different tank and, if they will let you, pick one with a recent inspection date. The inspections are good for 12 years. The company that runs the exchange should find the problem when they refill it.

I just went thru this when I went to get a tank refilled and the valve was bad, and they told me to just exchange the tank. So I'm not suggesting 'putting one over' on the propane company. BTW the inspection just consists of them looking at the tank before they fill it, a visual inspection.

[swimmer_spe]

downtheroad wrote:
Probably your tank was completely full and was sitting in the hot sun or in a hot shed/garage???
They do self-vent in these conditions...Once the pressure is reduced, (the tank cools some) they will stop venting..

Good that you are storing your tanks away from any flames like a water heater pilot light, etc.

It was in my garage. There is no flames in there unless I start up one of the many toys in there (atv, motorcycle, etc).

I will give it a day and see if it stops before I bring it back inside.

[downtheroad]

Probably your tank was completely full and was sitting in the hot sun or in a hot shed/garage???
They do self-vent in these conditions...Once the pressure is reduced, (the tank cools some) they will stop venting..

Good that you are storing your tanks away from any flames like a water heater pilot light, etc.