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Propane pressure relief valve?
Yesterday a friend camped near me with a LD asked if he could look at my propane system.  It seems he went into town for a fill and was turned away, when the technician fearfully told him he didn't have a pressure relief valve.  Well, his is the same as mine.  Neither of us has encountered this previously.

He is checking with the factory, who so far has handed him off to the manufacturer of the propane valves and regulator.  Meanwhile, I have been researching the issue. 

My best guess at this point is that our propane fill valve MAY be a Rego 7647SC fill valve with integral pressure relief.  I can't find any confirmation, nor can I find any documentation on line that this valve does in fact include an internal pressure relief valve.

Can anyone steer me to some definitive information?  If this can be nailed down, I want a piece of paper that I can show to someone in the event that they tell me that they can't fill my tank due to a lack of a pressure relief valve.

Thanks

Ken F in NM
'08 MB
Re: Propane pressure relief valve?
Reply #1 –
Same of the operators of propane stations are trained to look for certain things. If the tank does not match the model they learned on they will not touch the tank.

I have been rejected twice because my class "B" 6811 tank wiggles too much when the fill hose is attached.
Rodney
1988 Mid Bath
Re: Propane pressure relief valve?
Reply #2 –
Ken, was this information received from a propane supplier (as opposed to a gas station guy or somebody at an RV park or a U-Haul or.... )? In my experience, quite a few propane "fillers" aren't exactly up to speed when it comes to LPG savvy!  :o

I can't speak to any specifics with your system, or for mine, either, as the only LPG literature that I found in the packet for my 2003 was for the Marshall Brass regulator. Marshall Brass is now "Marshall Excelsior"; you might look at their site and that of Manchester tank for more information:

Welcome to Marshall Excelsior Company

DOT Tanks Propane Tanks Compressed Air Tanks ASME Grill Manufacturer

Please post a follow-up when you figure this out!
2003 TK has a new home
Re: Propane pressure relief valve?
Reply #4 –
Well, friend Tim found the answer.  The pressure relief valve is near the bottom of the tank.  NOBODY looked for it there.  I was looking near the top, thinking that vapor, rather than liquid, should be released.  Anyway, we now know - it is near the bottom of the propane tank.

Ken F in NM
'08 MB
Re: Propane pressure relief valve?
Reply #5 –
Do enlighten the propane guy! 😜
2003 TK has a new home
Re: Propane pressure relief valve?
Reply #7 –
Yes, the relief valve is just a plug, on the bottom of the tank.
Once it blows, the tank gets replaced, assuming your LD doesn't burn to the ground in the process..

What causes the fill stations to hesitate is a heavily rusted tank.
Many LDs have badly rusted tanks, the result of poor bonding between the metal and epoxy paint.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Propane pressure relief valve?
Reply #8 –
Quote from: Larry Wade  - 
Yes, the relief valve is just a plug, on the bottom of the tank.
Once it blows, the tank gets replaced, assuming your LD doesn't burn to the ground in the process..

What causes the fill stations to hesitate is a heavily rusted tank.
Many LDs have badly rusted tanks, the result of poor bonding between the metal and epoxy paint.

Larry

Larry, do RV propane tanks require occasional recertification?
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: Propane pressure relief valve?
Reply #9 –
Quote from: HiLola  - 
do RV propane tanks require occasional recertification?
Older LDs, mid-80s and older, had 40-lb removable bottles, similar to they cylinders used for home BBQs, except they are twice the size. They have the same certification requirements, needing pressure testing and recertification every twelve years.
To fill our 1983 22' FL's propane tank, it needed to be removed. Dang, a full 40-lb cylinder is hard to handle.
I would not want to too that today. Older LDs are for young people.

The newer, frame mounted, horizontal tanks surprising do not seem to have the same certification requirement. It's up to the technician, who is filling the tank, to determine if the tank appears to be in good operating condition. Heavy rust is a reason not to fill a tank.

I have seen many rusted propane tanks, some where the whole tank needs preparation and painting. Rigs operated on salted roads are the worse. Our western gravel roads do a good job of chipping the paint. Once chipped and rusting, the rust continues working its way under the paint and up the sides of the tank.
The fix is to yearly chip any loose paint, sand any bare metal, use a rust converter and then paint.
I have used Naval Jelly forever and it seems to work as well as other converters. Eastwood is another that works.
They all use a similar chemistry.

Larry


Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Propane pressure relief valve?
Reply #10 –
Propane tanks do require recertification.
The rules just changed. Check Issues 780 and 781of RV travel.com.  I think the portable cylinders need requalification after the first 10 years.  The mounted ASME cylinders need requalified after the first 12 years. External requalification is good for 5 years. Internal qualification is good for 7 years. 
Rodney
1988 Mid Bath
Re: Propane pressure relief valve?
Reply #11 –
Quote from: rodneyhelfrich  - 
Propane tanks do require recertification.
The rules just changed. Check Issues 780 and 781of RV travel.com.  I think the portable cylinders need requalification after the first 10 years.  The mounted ASME cylinders need requalified after the first 12 years. External requalification is good for 5 years. Internal qualification is good for 7 years.
I Read RV Travel.com's issues 780 and 781.
The only thing found, pertaining to propane tanks, was the new rules effecting the portable propane tanks only,  the type mounted on the front of trailers or used for home BBQs. Nothing was mentioned about frame mounted tanks.

Here is what was said in issue 781
"Last week, we published news regarding changes made to portable propane cylinder requirements. Again, let’s stress the fact that these new federal regulation changes apply only to PORTABLE propane cylinders – the ones typically found on travel trailers, fifth wheels and truck campers. They DO NOT apply to permanently mounted tanks found on motorhomes."

It's disruptive it when sites, such as RV Travel.com, do not bother to include any references or links to actual new regulations.
Are the 'rules' real or just rumors?

Checking the US Department of Transportation's website, nothing was found pertaining to new regulations of the horizontal, frame mounted tanks, used in RVs.
Here is what was found. It pertains to portable tanks.
http://www.phmsa.dot.gov/staticfiles/PHMSA/DownloadableFiles/Files/Hazmat/requal_propane_cylinders.pdf

So, if anyone has actual links to a Federal site showing new regulations for horizontal propane tanks, please links.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Propane pressure relief valve?
Reply #13 –
Propane cylinders, such as the familiar ones used for grilling, are subject to recertification and expiration regulations.

Propane tanks, such as are mounted on modern LDs, are not.

Mark H
Former owner, 31-foot gas Class A
Former owner, 1997-8 mid-bath