Author Topic: Propane flow problem  (Read 4749 times)

Offline FolkBus

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Propane flow problem
« on: March 06, 2014, 06:50:51 AM »
I have an interesting problem..  When I turn on any appliance in the coach, it will run fine for 2-3 minutes or so then the pressure will drop off to a very low flow then stop.  I turn the appliance off for a few minutes then turn it back on and the same thing happens.  I have blown out the propane lines with compressed air. I have changed out the regulator. No change. The tank is a permanently mounted horizontal 40 gal with a center fill and valve.  Could the valve have gone bad?  it is NOT an OPD valve.

I'm running out of airspeed and ideas.  Thoughts??

As usual thank you for all the thoughts and ideas.  This forum is a great font of information.


--Mike
Mike and Debbie McNeil  Ridgway - Montrose, CO
1949 Crown SuperCoach (Amazing Grace) Conversion 1972  Pancake 220 Cummins  Fuller 5 Speed

1967 MC-5A  (Serenity)  Conversion 1986  8v-71N   Allison MT-644

Offline luvrbus

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Re: Propane flow problem
« Reply #1 on: March 06, 2014, 06:59:58 AM »
If you are using a BBQ hose it has a excessive flow valve built in that will shut the propane off and yours could have one even with cooper lines check the nut and a look for the flow valve inside the nut,I usually drill the valve out myself fwiw
Life is short drink the good wine first

Offline Bob Gilbert

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Re: Propane flow problem
« Reply #2 on: March 06, 2014, 09:35:54 AM »
some permentely mounted lp thanks have a internal filter/screen, found it to be a problem on a lp powered combine. Hope this helps

Offline wg4t50

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Re: Propane flow problem
« Reply #3 on: March 06, 2014, 11:00:35 AM »
Would first check to see it the regulator is freezing / frosting up, yours                   sounds like this issue.  Is caused by cold temp, small tank and drawing more fuel than it can vaporize, causing the frosting of the regulator.  A common problem with generators on LP Gas  with cold temp and heavy loading.  the units running on LP Liquid do not suffer this as much
When the regulator frosts up, it is simply because your using more fuel than it can vaporize, as the temp falls the larger the tank needs to be. if this is a new issue or an on going one.
Put some heat in the area of the LP tank, no open flame, just a heater, might help if it is a frost issue.
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Offline Jeremy

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Re: Propane flow problem
« Reply #4 on: March 06, 2014, 01:03:26 PM »
I would guess at freezing being the problem as well - having converted my Range Rover to run on LPG I know that the vapourisers are plumbed-into the engine's cooling system to keep them warm in order to prevent this issue.

Jeremy
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Offline Lin

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Re: Propane flow problem
« Reply #5 on: March 06, 2014, 01:58:05 PM »
As asked above, is this a new problem on a system that has previously worked fine? 

Regarding the possibility of the regulator freezing, check to make sure you are drawing from the tanks vapor port and not a liquid port since some tanks have both.  All of the regular appliances like stove, furnace, etc. should draw vapor.  Very large consumers, like engines, will generally draw from the liquid port and require a vaporizer inline.
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Offline busguy01

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Re: Propane flow problem
« Reply #6 on: March 06, 2014, 03:02:04 PM »
Where did you last fill?? Had mine filled some years back in a warm area then had same problem when I was in a colder area - found that they had filled with a mix of propane and butane. Butane will freeze your regulater at about 32 degrees! Only cure was to drain and refill with pure propane.
The reason tis happens is that butane is a LOT cheaper than propane - which is really high $ right now.
JimH
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Offline robertglines1

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Re: Propane flow problem
« Reply #7 on: March 06, 2014, 03:40:33 PM »
The guys pretty well covered everything.  One point regulator are vertical or horizontal mount .  sometimes guys get away with them mounted wrong for years then have problems.. should be marked.  FWIW.
Bob@Judy  98 XLE prevost with 3 slides --Home done---last one! SW INdiana

Offline luvrbus

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Re: Propane flow problem
« Reply #8 on: March 06, 2014, 03:47:34 PM »
The excessive flow valve has been bad for me every time I had a problem only thing one never knows where it is located some times at the tank,regulator,tank nut or inline www.lp-gasequipment.com

good luck
Life is short drink the good wine first

Offline robertglines1

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Re: Propane flow problem
« Reply #9 on: March 06, 2014, 04:27:31 PM »
Was this the first time you tried to use this set up??First use/fill of new install?
Bob@Judy  98 XLE prevost with 3 slides --Home done---last one! SW INdiana

Offline FolkBus

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Re: Propane flow problem
« Reply #10 on: March 07, 2014, 05:27:17 AM »
Thanks everyone. I now have lots to check and try.  The PO had passed away when I bought this coach so I do not know the propane history. However this system has been a problem since I have had it.

On the road for a couple of weeks for work (flying, darn it) looking forward to working on this when I get back.

--Mike
Mike and Debbie McNeil  Ridgway - Montrose, CO
1949 Crown SuperCoach (Amazing Grace) Conversion 1972  Pancake 220 Cummins  Fuller 5 Speed

1967 MC-5A  (Serenity)  Conversion 1986  8v-71N   Allison MT-644

Offline gus

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Re: Propane flow problem
« Reply #11 on: March 07, 2014, 03:57:57 PM »
Those newer valves have to be opened very slowly to keep them from shutting down.
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Offline Jriddle

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Re: Propane flow problem
« Reply #12 on: March 07, 2014, 05:49:13 PM »
Those newer valves have to be opened very slowly to keep them from shutting down.

Especially if the line is empty the tank will think you have a leak and shutdown.

John
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1984 MC9

 

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