Newly-filled Propane Tanks empty in four days-not used much

[CarolineGates]

I am back, pretty sure I got my breaker problem resolved. Now I have a new one with my 2010 Cougar. I have two 7-gal propane tanks, one on each side of the front end of the rig. I use propane only for furnace and stove and seldom use either as I prefer elec/microwave/gadgets etc. I went to turn on the furnace during a cold spell we just had and it was empty. OK, got the two filled up and installed them. Forgot to turn on furnace at 65 degrees over Thanksgiving, so it did not use propane then. Since then I have kept it at 65 degrees and on but it doesn't come on because I have my space heaters going and they keep rig warm. So I use furnace only in the a.m. at 75 degrees, then down again to 65 and it doesn't come on. My point is that I have not used up any of the propane I bought just before Thanksgiving. The red marker shows them empty. We have used the soap method to check for leaks on/around the tanks. All looks good. Local dealer said even with bubbles those tanks would lose only a small amount if they were leaking. One person smelled propane near the tanks. Dealer also said someone probably stole the tanks by switching them with empties. I tried to turn on the stove burners and there is no propane in those lines. The stove has hardly been used. Two summers ago someone came into our RV park where I and many others live full time and stole the gas tanks out of three river boats during the night right under bedroom windows (it was windy/raining) so I guess someone could have switched. What I am going to do about this is fill the front/main propane tank again, install it, turn the secondary off completely so it won't transfer over, and see what happens. I did run the furnace yesterday a.m. for 15 min. That's it. Turned it on again this a.m. and the furnace started, air blew out, no heat came out, and furnace shut off. That is when I checked the tanks, both empty. My question, after all of that, is between the tanks and the furnace and stove, which are close to each other, could there be any kind of leak problems that would use 14.2 gal of propane up and I am still alive having been inside this rig most of the time? I can't smell anything due to sinus surgeries, so I have to depend on others. Thanks

[TakingThe5th]

CarolineGates wrote:
I think I have found the problem why my newly-filled propane tanks emptied out in hours. We found that the exterior quick disconnect to LP was leaking. We closed the ball valve on it and I didn't lose any more of the propane tank I had to fill after the original two emptied. My furnace is working normally.

Glad you found the problem. I think we have a "two-fer answer here - someone on another post was wanting to install a quick disconnect inside for a small space heater and wondered if it might leak. Here is one answer-yes.

[Me_Again]

Great! There is alway a reason. Sometimes it is just difficult to locate it. Chris

[CarolineGates]

I think I have found the problem why my newly-filled propane tanks emptied out in hours. We found that the exterior quick disconnect to LP was leaking. We closed the ball valve on it and I didn't lose any more of the propane tank I had to fill after the original two emptied. My furnace is working normally.

[Sport45]

Keep in mind that even a "full" propane cylinder or tank won't hit 350 psi until the bulk temperature is around 150°F.

I suppose if you paint one black and leave it in full sun you might get it to vent. But as long as they are shaded and reasonably protected there isn't a problem.

[plauterer]

Camped out for five nights this November. Well below freezing every night. Had a generator going all night and used a 800 watt heater. The furnace was set at 70 degrees. burnt up 25 pounds of propane. I generally weigh my tanks so I know how much fuel I have. In Canada the tanks have to be re-valved every 10 years. A new expiry date is stamped on the neck.
I wonder if your propane was in fact mostly butane. Butane stops evaporating when it gets cold.
Also when you get liquid propane on you hand that is not a burn, that is instant frost bit.

[Allworth]

I'm too old for really cold weather camping now, but when I used to do Engineering and Survey work in very cold places we put a 25W light bulb on a drop cord in the compartment with the regulator on the office trailers to prevent icing. Just a few degrees of heat prevents it.

[Old-Biscuit]

Larryzv7 wrote:
Old Biscuit, thanks for the info and the drawing. Now I am also told that propane tanks have an expiration date stamped on them. Further low temperature outdoors can diminish the efficiency of a propane system. Anytime a propane tanks’ pressure exceeds 350PSI the pressure relief will begin releasing propane vapor. So smelling propane may not necessarily mean that you have a leak. Can anyone verify these statements to be true or false? Thanks!!!!

Propane 'cylinders' (portable type 4-40#) have a re-certification requirement. 12 yrs. after mfg. date stamped on collar they must be 'visually inspected' (good for another 5 yrs) or 'tested' (good for another 7 yrs). New date sticker applied. This is a DOT requirement
(Propane TANKS ----MHs-----do not have this re-certification requirement. They are an ASME/NFPA jurisdiction vessel)

Yes relief valve will open at 350# and spew vapor. If vertical cylinder is laid on it's side relief valve is now in liquid and if it should open liquid propane would be spewed. Liquid propane will burn you on contact.

Propane liquid boils (turns to vapor) at -44*F so you have to have extreme cold temps to really affect propane

Low temps can cause issues with flow thru regulator and cause 'icing' at regulator. Simple insulation of regulator will take care of that-----but if icing occurs you should have cylinder 'purged' to remove any entrained moisture/air OR butane mixture.

[Larryzv7]

Old Biscuit, thanks for the info and the drawing. Now I am also told that propane tanks have an expiration date stamped on them. Further low temperature outdoors can diminish the efficiency of a propane system. Anytime a propane tanks’ pressure exceeds 350PSI the pressure relief will begin releasing propane vapor. So smelling propane may not necessarily mean that you have a leak. Can anyone verify these statements to be true or false? Thanks!!!!

[shepstone]

CarolineGates wrote:
Shepstone, what did you do to fix the problem that you say is similar to mine?

I had to keep swapping tanks over until I got a new regulator

[Memphisdoug]

Check your rubber hoses. My girl friends sister had a squirrel or chipmunk chew a hole thru one of hers.

[Old-Biscuit]

Larryzv7 wrote:
This discussion is very interesting. I was told that when they refill a propane tank it is never filled completely; there is always room left for some air. Is this correct? Also that you should regularly bleed your propane tanks of air until a white mist starts coming out. Don’t know if that’s correct either?

Thought I’d mention that I put a small lock on both my propane tanks because I have heard of people stealing propane tanks off an RV while the owner is sleeping or away from their campsite.

Propane vessels are filled to 80% capacity .....that 80% is FULL liquid level
The other 20% propane VAPOR....no air
Bleeder valve has a tube that goes down inside to the 80% Liquid level.
When filling bleeder is cracked opened until liquid spits out indicating liquid level is at 80% mark

NO you do not have to 'vent' air off occasionally as there is NO air in a properly filled propane vessel (cylinder or tank)

[CarolineGates]

My propane tanks are always filled at my Union 76 station here in Bandon, OR.
They have a huge tank and know what they are doing. I just got two small locks at Ace Hdwe to attach to the bands around my tanks. It won't keep someone from being aggressive to take your tanks, but I think it will stop someone who thinks they might get caught. They will move to the next victim. These are small tanks.

[Larryzv7]

This discussion is very interesting. I was told that when they refill a propane tank it is never filled completely; there is always room left for some air. Is this correct? Also that you should regularly bleed your propane tanks of air until a white mist starts coming out. Don’t know if that’s correct either?

Thought I’d mention that I put a small lock on both my propane tanks because I have heard of people stealing propane tanks off an RV while the owner is sleeping or away from their campsite.

[SteveB]

Late to this party but...
I had my 12 year old regulator bite the dust over Memorial weekend camping. Brand new tank would not flow. I was lucky that one side still worked enough so I put the full tank on that pigtail. If the OP tanks are "light" then it seems pretty obvious there's a leak but if they are still heavy it could just be a bad regulator.