Slow Propane

jamesw · 07-24-2011, 11:13 PM

I just recently got a used Flagstaff 206LTD. We set it up in the driveway and everything was working fine but when we took it out this past weekend for a little test trip before the week long vaca we had trouble getting the fridge, heat, and propane to work properly. It seems like the propane is not flowing fast enough. My wife had a pot on the stove that never seemed to boil even though we had flame. I have had to my father in law and a family friend look at it with no solution. They both have worked their way up from these pop-ups and now have a 5th wheel and motorcoach. I have never had anything but a tent, therefore am new to RV camping.
I figured this forum would be the best way to go seems how the manual I have doesn't seem to even be for my unit. Any help would be greatly appreciated. I'll tackle this issue first and will most likely have a lot more to ask in the future Thanks.

bean · 07-25-2011, 06:37 AM

When you turn on the propane, do it SLOWLY. There is some kind of safety valve that kicks in if too much propane tries to leave the tank quickly.

When I've had this problem I've had to open the relief valve on the tank (recessed straight head screw) and let some gas out. Then turn it on again slower.

Bean

**KyDan** · 07-25-2011, 06:45 AM

What he said.
There is a safety valve on all new tanks. It's supposed to sense a failure
like a blown hose and shut off or shut nearly off.
Occasionally a tank will activate the safety valve when it is first
opened and is trying to pressurize your system.
The fix is to shut off all gas appliances and shut the tank and wait a second
or 2 and then slowly open the valve.
You might unstick a stubborn safety valve by tapping the tank
with a hammer handle or bump it with a piece of fire wood.
Just a good tap should do it.

Sometimes I think if they make things any safer we'll not be able to use them!

jamesw · 07-26-2011, 03:05 PM

So to be clear...the safety valve can cause a slow flow? You would think it would be safer to shut off the gas completely.

MtnGuy · 07-26-2011, 03:18 PM

Quote:

Originally Posted by jamesw

So to be clear...the safety valve can cause a slow flow? You would think it would be safer to shut off the gas completely.

It should shut off the gas completely, but that doesn't mean that it might leak some, hence the slow flow.

jamesw · 07-26-2011, 03:20 PM

Which means that I have a faulty valve either way.

MtnGuy · 07-26-2011, 03:31 PM

Check out this website: Propane Safety and Use

About half way down, beside the photo of the pigtail, is an explanation of how the safety systems work. Under that is "How to Fix the Situation" (low propane flow). Try that remedy and see if that helps.

frankm · 07-26-2011, 03:37 PM

Just about everything you ever wanted to know about LP gas can be found here, Propane 101 - Promoting Propane Safety Through Understanding

fordmantpw · 07-26-2011, 04:20 PM

Quote:

Originally Posted by jamesw

My wife had a pot on the stove that never seemed to boil even though we had flame.

Was she watching the pot? Because, you know, a watched pot never boils!

Sorry, I can't help with your situation, but wanted to attempt to add a bit of humor! Sorry if I failed.

The_Stuff · 07-26-2011, 04:41 PM

also make sure when you fill your propane you fill up both tanks. mine wouldn't work worth a darn with only one tank full... and ya, turn them on slowly.

**KyDan** · 07-28-2011, 07:22 AM

On a previous trailer on a COLD late fall middle of the night-
I had only turned on one tank valve.
Naturally the LP ran out in the wee hours of the night.
I got up and tossed on some clothes and went outside and spun the
valve open on the 2nd tank. It was full.
I went back inside and found the furnace was not working.
I lit a stove burner and got a small flame.
I went back outside and shut the tank swapped positions with the
empty one and tried it again and it worked.

In retrospect I'm pretty sure I just opened the valve on the full tank
too fast and the safety valve shut it off or nearly off.

On my home back patio gas grill, if I turn on the burner 1st and then
spin open the tank valve it will occasionally trigger the safety valve
and when that happens I get a low flow and small burner flame.
Cure is to shut the burner off and shut the tank and wait a second
and then open the tank slowly and everything is back to normal.

I don't know what the website says about the safety valve but my
real life experiences are that they do shut the tank but not all the way.
Many folks have posted here over the years that had the same thing.
Low flow rather than no flow seems to be the norm when the safety
valve is activated usually by spinning the hand valve open too fast
on a system that has no pressure.

MtnGuy · 07-28-2011, 07:45 AM

Dan, just speculating here, but your incident could also be be caused by the "flow limiting device". There is an explanation on that with my #7 post link.

If you turned on the 2nd cylinder, and the furnace was still calling for propane, then the flow limiting device will not open fully. It needs back pressure to completely open. Somewhere between swapping cylinders, maybe the furnace shut down and was no longer calling for propane, the system had enough back pressure, and the flow limiting device fully opened. Even an open oven pilot light valve is enough to trigger the flow limiting device into not opening fully.

Of course, it could have been just as you said.....the tank was opened to fast allowing the OPD to shut off the flow on a full tank.......in that case my long winded explanation above is a moot point.

Ideally, the OPD should shut the gas off entirely, and only close when the tank gets full at filling. That is because once a pigtail is screwed onto the tank, the OPD valve should stay open, regardless. Of course, that is theoretical.

The flow limiting device will give a low flow situation if there is not proper back pressure.

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