Michele Williams on wed 24 apr 02
Propane valves and re-certificationClaybuddies,
Those of you who use propane for firing your work may find the following =
article useful. My husband found it and I have already thanked him for =
you.
Michele Williams
Propane Tank Valves and Re-Certification
David E. Damouth
(revised: 6 Feb. 2002)
This is a revision of an article originally written in late 1999. It =
contains general information about propane tank recertification =
requirements and about the requirement that new tank valves be installed =
before April 2002. =20
The following applies to vertically mounted propane tanks with 4 to 40 =
pound capacity. Previous versions of this article made a distinction =
between DOT tanks (portable, available in both vertically and =
horizontally mounted versions) and ASME tanks (permanently mounted, =
generally larger, and horizontally mounted only.) Recent information =
makes it clear that this distinction can be ignored when considering =
requirements for the new OPD valve. It is now clear that the only =
important distinction is that all vertically mounted tanks with capacity =
between 4 and 40 pounds must be refitted with OPD valves. All tanks =
over 40 pounds are not subject to the new rule. =20
Note added 6 Feb. 2002: Horizontal DOT tanks of less than 40 pound =
capacity have recently been granted a special exemption from the OPD =
requirement. See Horizontal Exemption, below. My thanks to "Sandy =
McClymont" mcclymo@attglobal.net for discovering and forwarding this =
new information.=20
About DOT tanks:
The most common portable tank is called a "DOT" tank, since it is built =
to conform to design and usage regulations established by the Federal =
Department of Transportation. Both horizontally and vertically mounted =
portable DOT tanks are available, although the horizontal tank is much =
less common. The horizontal and vertical tanks are not interchangeable, =
and must be stored, filled, and used only in the specified horizontal or =
vertical mounting position.=20
DOT tanks may only be used for 12 years after the manufacturing date. =
(This is according to a standard created by the National Fire Protection =
Association, and adopted as law by most states). Some states may have =
adopted rules which specify a different period. A dealer in Minnesota =
claimed that the state only allow 10 years). After that, tanks must be =
"re-certified", giving another five years (and can be recertified =
repeatedly, every five years). My tanks were manufactured in December, =
1987, so I needed to get them recertified or replaced by the end of =
1999. (As of January 17, 2002, a great many states have not yet adopted =
the new rule requiring OPD valves, and a few have adopted an early =
version of the OPD rule which does not exempt horizontal cylinders. For =
specific state information, see the table at the end of =
http://www.npga.org/public/articles/OPD_Packet.pdf
Propane dealers are legally required to look at the date stamped on the =
tank before filling it. Some of them actually do look. I've now been =
reminded several times by dealers that my tanks were about to expire. =
Recertification can only be done by the large bulk propane suppliers, =
not by typical small dealers. Beginning April 1, 2002, dealers in many =
states will also have to verify, before refilling a tank, that vertical =
tanks between 4 pound and 40 pound capacity have the new OPD valve =
described below.
The National Fire Protection Association has recently outlawed the POL =
valves found on nearly all older DOT tanks. (POL is an acronym for =
Prest-O-Lite, the company which introduced this valve in about 1920). =
These valves are what almost all of us currently have - they have the =
familiar female left-hand-thread in the valve. Tanks with this type =
valve must now have the valve changed to a new type of valve during =
recertification, may not be sold beginning in 2000, and may not be =
refilled beginning April 1, 2002.
The POL valves are being replaced with a new type which uses a QCC =
(Quick Closing Coupling) connector. This connector has an external =
(male) right-hand thread on the valve. A hose can be connected and =
disconnected by hand - no wrench required. These valves also have the =
old-style POL internal left-hand thread, so they can be used directly in =
place of the old tanks without modifying the old hoses on your RV. If =
you like the no-tools convenience of the new style connector, or still =
have trouble dealing with a left-hand thread, you may also want to =
replace your hoses with new ones having the QCC connectors. But you can =
do it later - it doesn't have to be done at the same time you replace =
the valve.
The new valve also contains an OPD (Overfill Protection Device). So they =
may be called either OPD valves or QCC valves, depending on the whim of =
the supplier. The OPD feature makes it more difficult for the typical =
under-trained, uninformed, or incompetent attendant overfill the tank. =
An internal float mechanism shuts off the valve when the tank is 80% =
filled. The 20% empty space is necessary to prevent the tank from =
venting large amounts of propane when the temperature rises. This new =
OPD feature is not to be used as the primary overfilling control. =
Rather, it is strictly a backup safety device, and filling is to be =
controlled primarily by weight or by the "dip tube" bleeder valve which =
indicates 80% fill. =20
The new OPD valve also contains another important safety feature - it =
will not release gas unless the hose is properly connected, even with =
the valve open.
It is still possible to overfill the tank if the tank is not vertical or =
if the OPD float valve malfunctions (there have been reports of OPD =
devices not working properly). For this reason, it is still a good idea =
(and required by the new code) to monitor the weight of the tank or the =
number of gallons dispensed or the 80% bleed valve, not depending =
exclusively on the OPD device. The technician who filled my new tank =
monitored the weight of the tank, and verified that the OPD device shut =
off the propane flow just before the tank reached its specified 80% =
capacity. (The old "dip tube bleed valve" still exists in the new =
valves. By slightly opening a vent on the side of the valve (with a =
flat-blade screwdriver), one knows when the tank is 80% full because =
liquid propane begins spurting out this vent.) So there are several =
independent ways of verifying that a tank is properly filled. Be sure =
that more than one of these ways is used, particularly with a new tank, =
but preferably with every fill.
In the East, almost everyone who dispenses propane has a scale, and =
monitors weight of the old tanks during filling. This still works fine =
with the new tanks. In the West, many places don't have scales. With old =
tanks, they depend on the dip tube vent and a measure of gallons =
dispensed. Some of these people are lazy and now depend *only* on the =
OPD valve (which is not legal). When filling an OPD tank that wasn't =
completely empty, this provides no useful backup indication in case the =
OPD device fails - somewhat unsettling. This won't affect me personally, =
since I always wait until a tank is empty before refilling.=20
The ASME tanks have been using an earlier type of OPD float for about 14 =
years, and are usually refilled when only partially emptied. If a =
significant number of float failures have occurred, I'd expect that =
we've have heard about it. I wonder if the float mechanism on those =
tanks is different and more reliable?
Replacement or Recertification: =20
In October, 1999, as my recertification deadline approached, I asked =
around to find the best way to upgrade or replace my tanks. New 30 pound =
tanks cost about $50 at a large propane distributor and up to $70 at RV =
stores. This is for an *empty* tank.
One propane dealer quoted me a price of $35 to install a new-style valve =
and recertify my existing tank. This would require dropping off my tanks =
and picking them up at some time in the future (I'd have to get along =
without propane in the trailer in the meanwhile, or else make two trips =
there and back, leaving one tank at a time). And this price doesn't =
include a propane fill.
I found a much better deal, in the Finger Lakes region of New York. =
Ballantyne RV, in Victor, NY, had a supply of reconditioned tanks which =
they exchange for an old tank. I bought a reconditioned 30-pound tank, =
with new OPD valve, re-certified, repainted, already full of propane, =
for $21.39 (including 7% tax). Unfortunately, they only had one 30-pound =
tank in stock, and said that their supplier wouldn't be delivering more =
for at least 10 days. (They had plenty of 20-pound tanks).
A week later, when I emptied my other old tank, I drove to the supplier =
- Phelps Sungas, Inc, whose main distribution center is about 5 miles =
north of Geneva, N.Y. They have a huge supply of tanks, and sold me =
another reconditioned tank, full, for $29.09 (including tax) in exchange =
for my old tank. This price feels about right. I suspect the lower price =
at Ballantyne was either a mistake (although the price was posted on the =
wall) or an obsolete price. It seems too low, considering that a propane =
fill alone at that time was costing between $11 and $18.=20
Phelps has two other branch locations in the Finger Lakes, but doesn't =
stock 30-pound reconditioned tanks at the branches. They also probably =
supply =3D other RV dealers in the area with tanks for exchange.
I don't know if this kind of exchange deal for 30-pound tanks is =
available elsewhere in the country, but it is certainly worth hunting =
for. Exchange of 20-pound tanks is quite common at lawn and garden =
centers, large hardware stores, and other such places all over the =
country, but this is the first time I'd seen it offered for 30-pound =
tanks. Be careful - the usual exchange place may give you a tank with an =
about-to-expire certification and with an old-style valve unless you =
specifically ask for an OPD valve and you personally search through =
their stock looking for a recent certification.
The new valve is easily recognizable. It has a triangular valve handle =
and large external threads at the hose connection. The date of =
manufacture (and date of recertification, if this has been done) is =
stamped into the metal near the top of the tank, and is a numeric month =
and year (1287 means December 1987).
Don't forget that you will lose any propane in your old tank when you =
take it in for a new valve or for exchange. Do it one tank at a time, =
when the tank is empty.
I've heard that Home Depot and other such places now sell a replacement =
OPD valve for about $11, allowing you to replace your old valve =
yourself. It's worth checking this option if you are a DIY type of =
person - but you'll still need to pay for recertification when your tank =
is 12 years old. Note that these replacement OPD valves are only for =
vertical tanks. There apparently are no replacement OPD valves for =
horizontal tanks - hence the exception reported below.)
Why OPD? The scuttlebutt is that safety was not the primary reason for =
changing to the new valve. The real reason apparently is that the =
backyard barbecue folks couldn't learn to deal with left-hand threads. =
Once the decision was made to change the connector, then throwing in the =
new safety features came almost for free. (The references below seem =
to contradict this rumor - but it wouldn't be the first time that =
history has been rewritten).
Miscellany:
The new connectors are great: I have now replaced both tank hoses with =
new hoses and QCC connectors. These new connectors are a major =
convenience for anyone who uses a lot of propane. They are much easier =
to attach and detach and require no tools. (When boondocking in cool =
spring and autumn conditions, where nighttime temperatures may be near =
freezing, we use about one 30-pound tank of propane per week). RV =
stores have these replacement hoses available, in various lengths. I =
got mine at Camping World for about $10 each. Installation is trivial - =
requiring only a small wrench, and a little Teflon tape to seal the =
threads (available anywhere that sells plumbing supplies).
Barbecue Adapter: Do you have one of those adapters which fits between =
the propane tank and the connector hose, which has a quick-connect =
fitting for a hose to your barbecue grill? The old ones won't work =
with the new QCC hose! New adapters with QCC fittings weren't yet =
available in the stores in October 1999 (they are available now). But =
my adapter had always been a problem anyway - it was so long that it was =
difficult to get the plastic tank cover down over the hoses with the =
adapter in place, and the cover forced the tank hose into a very sharp =
bend - a longevity concern. =20
The solution turned out to be simple. I removed the old POL valve =
adapters from each end of the Quick-connect fitting, and bought new =
adapters which allowed me to screw the quick-connect fitting directly =
into the pressure regulator, and then screw the new QCC hose (the end =
that was intended to go into the regulator) directly into the input to =
the quick-connect tap. If you can't find the right adapters, it's easy =
to cut the existing fitting off the end of the QCC hose and insert a new =
fitting (hose barb on one end, fastened with a tiny stainless steel hose =
clamp, and a 1/8" or 1/4" National Pipe Thread on the end that goes into =
the regulator. Works fine, and is a whole lot more compact, neater, and =
more elegant, than the old arrangement. Total cost for the conversion =
was a couple of bucks for adapters at a local hardware store.=20
Recent Exclusion of horizontal DOT tanks: Owners of older RV's that use =
horizontal rather than vertical propane cylinders should read the =
following information:
The new OPD (Overfilling Prevention Device) valves will be required on 4 =
lb. to 40 lb. propane cylinders from 1 April 2002. However, the =
currently available new valves are designed only for vertical cylinders =
and cannot be used with horizontal cylinders. Therefore, horizontal =
cylinders manufactured prior to 1 October 1998 have been exempted from =
having OPD valves, provided they are so labeled. (Such cylinders =
manufactured after 1 October 1998 do already have OPD valves).
This information is on the website of the National Propane Gas =
Association. See A pamphlet addressing commonly asked questions from =
propane consumers..
Since propane dealers do not seem always well-informed, it is suggested =
that RV owners with pre-1998 horizontal DOT tanks should print this =
article and carry it with them, in case a dealer balks at filling a =
cylinder without an OPD valve.
The relevant part of the document is on the second page:
Q: I have a horizontal cylinder on my recreational vehicle. Are =
OPD's available for that kind of service? =20
A: The 2001 edition of NFPA [National Fire Protection Association] =
58 (the LP-Gas Code) recognizes that horizontally oriented cylinders =
that were manufactured prior to October 1, 1998, are unable to be =
retrofitted with the OPD's. As a result of this fact, the Code now =
exempts these cylinders from having to be retrofit with OPD valves. Any =
such cylinder must have a label affixed to it to inform the user and the =
refiller that an OPD valve is not installed."
For more information on this general subject, see the following =
documents from the National Propane Gas Association:
(All of the following documents are in PDF format, and are opened using =
Adobe Acrobat Reader.)=20
a.. A brief history of the events which led to the adoption of the OPD =
requirements in the 1998 edition of NFPA 58.
b.. A primer on the legal implications of the OPD.
c.. A pamphlet addressing commonly asked questions from propane =
marketers. rev. 01/02
d.. A pamphlet addressing commonly asked questions from propane =
consumers. rev. 01/02
e.. A listing of each state's currently adopted edition of NFPA 58. =
rev. 01/02
(this very useful link is broken as of 2/6/02 - however, the document =
is also included at the end of the "all of these documents" collection, =
below)
(You may download all of these documents in one by clicking here.)
Back to Tip Menu
all rights reserved; permission granted to copy, for personal =
non-commercial use, the complete unmodified document including this =
notice; copyright: 1999, 2000, 2002 by David E. Damouth =
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