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[GMCnet] LPG tank pressure relief valve testing [message #156411] Wed, 11 January 2012 21:14 Go to next message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
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Senior Member
G'day,

Should we add a step to the GMC Fire Guide on the Eastern States Website to pressure test the relief valves on the LPG tank in our
GMC's?

They are all over 30 years old!

If the consensus is yes we need to figger out how to do it safely; would it be safe to pressurize it installed in the tank or not?

If it is OK to leave it installed is it OK to use compressed air.

IIRC if you open the propane tank is allowed to fill with air it must be purged with propane or evacuated and backfilled with
propane to get all the air out.

Regards,
Rob M.

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] LPG tank pressure relief valve testing [message #156484 is a reply to message #156411] Thu, 12 January 2012 14:45 Go to previous messageGo to next message
Greg and April is currently offline  Greg and April   United States
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Registered: December 2011
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Senior Member
Rob,

I agree that a safety valve check would be a good idea, but how to do it, in
a portable setting is a very good question.

The only thing I can come up with is to tell you how they did it at the
propane plant I worked at, and perhaps someone else might have an idea how
to use it.

They would empty the tank to be tested then use CO2 to purge any remaining
propane and then dismount the valve and pressurize it with more CO2 to the
working pressure - then reverse the procedure, remount the valve, purge and
pressurize the tank with CO2 again to make sure that there wasn't enough air
to support combustion and that they had a good seal on the remounted valve,
and then refill with propane.

Perhaps a rally not to far from a propane dealer, and folks could come to it
with empty or near empty propane tanks, have the valve tested and then
refill the tanks after the testing is done.
.

Greg H.

I don't just march to the beat of my own drum - I have an entire brass band
to keep me company.

.
----- Original Message -----
From: "Rob Mueller" <robmueller@iinet.net.au>
To: <gmclist@temp.gmcnet.org>
Sent: Wednesday, January 11, 2012 20:14
Subject: [GMCnet] LPG tank pressure relief valve testing


> G'day,
>
> Should we add a step to the GMC Fire Guide on the Eastern States Website
> to pressure test the relief valves on the LPG tank in our
> GMC's?
>
> They are all over 30 years old!
>
> If the consensus is yes we need to figger out how to do it safely; would
> it be safe to pressurize it installed in the tank or not?
>
> If it is OK to leave it installed is it OK to use compressed air.
>
> IIRC if you open the propane tank is allowed to fill with air it must be
> purged with propane or evacuated and backfilled with
> propane to get all the air out.
>
> Regards,
> Rob M.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Re: [GMCnet] LPG tank pressure relief valve testing [message #156521 is a reply to message #156484] Thu, 12 January 2012 19:44 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Greg,

Thanks.

Regards,
Rob M.


-----Original Message-----
From: Greg and April

Rob,

I agree that a safety valve check would be a good idea, but how to do it, in
a portable setting is a very good question.

The only thing I can come up with is to tell you how they did it at the
propane plant I worked at, and perhaps someone else might have an idea how
to use it.

They would empty the tank to be tested then use CO2 to purge any remaining
propane and then dismount the valve and pressurize it with more CO2 to the
working pressure - then reverse the procedure, remount the valve, purge and
pressurize the tank with CO2 again to make sure that there wasn't enough air
to support combustion and that they had a good seal on the remounted valve,
and then refill with propane.

Perhaps a rally not to far from a propane dealer, and folks could come to it
with empty or near empty propane tanks, have the valve tested and then
refill the tanks after the testing is done.

Greg H.

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GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist



Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] LPG tank pressure relief valve testing [message #156529 is a reply to message #156411] Thu, 12 January 2012 20:30 Go to previous message
mike miller   United States
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
Senior Member
Robert Mueller wrote on Wed, 11 January 2012 19:14

G'day,

Should we add a step to the GMC Fire Guide on the Eastern States Website to pressure test the relief valves on the LPG tank in our
GMC's?

They are all over 30 years old! ...


IMHO: It would be easier, and most likely cheaper, just to replace the valve.

IIRC: The relief valve is part of the shut off valve. I had the one on my '78 replaced a while back... I do not remember it being expensive.


Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com
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