Gas problem

[Jim K in PA]

Hi all,

I have a gas problem.  I know, I should tell my wife to stop eating so many onions, but that's not relevant right now . . .  

We picked up our NTU 2006 Viking last Friday.  We came home and set it up in the yard.  Eventually we got around to trying out the gas appliances.  Turned on the cook top burner and . . . nothing.  Fridge was the same.  I didn't even bother with the furnace.

Based on reading here and talking to a plumber friend, it seemed that the regulator was the likely culprit.  Now, the dealer actually left the prep sheet in the camper and there were detailed notes indicating that a leak test and pressure check was done.  So what the heck?

I took the regulator off the hard line and removed the flex line.  I was readily able to get air to move through the regulator.  OK, now what.

Ultimately I eliminated all other issues and was left with the flex hose.  It just baaaarely allows flow.  I even tried to pressurize it in reverse with my compressor.  No difference.

So, I returned here and searched again.  Per THIS THREAD I have deduced that my problem is the "leak detector/preventer" in the end of the hose.  It must have tripped, and is now stuck closed.

Is my only solution to replace it?

Sorry for the long winded post.

[AustinBoston]

So, I returned here and searched again.  Per THIS THREAD I have deduced that my problem is the "leak detector/preventer" in the end of the hose.

The "leak detector/preventor" is in the tank, not the hose.  If you can't get LP through the hose, it is likely clogged.

Note: If you hook the hose to the tank without the regulator and an appliance, it will trip the leak detector, and you will get very little gas through the hose, making it look like it's clogged.

Austin

[Jim K in PA]

AustinBoston

Thanks for the response.  However, I respectfully disagree with you that the leak preventer is in the tank valve. At least it is not on my two tanks that I have tried.  

Per the other thread dthurk said:

Was reading my manual last night (as if I had nothing better to do) and found the leak detector is in the pigtail that connects the tank to the regulator and is specific to the RV industry. We use a "Type 1 Excess Flow Pigtail". Maybe that bit of trivia will come in handy some day.

The following is from the manual:
To remedy a low flow or restricted flow condition:
1. Extinguish all flames and smoking materials.
2. Important: be sure all gas appliances, including their pilot lights, are off and gas is not flowing in the system.
3. Open the LP gas cylinder valve slowly. Do not snap open.
4. Be sure all connections have been tested with a soapy solution (non-ammonia dish washing liquid) or leak detector solution to assure the system is leak free.
5.Wait at least 15 seconds before lighting appliances.
6. If difficulties continue, have the system checked by a qualified RV service technician.

This is NOT from the manual:
Buy a gas grill pigtail and you may be able to bypass it. But would you want to?

MY pigtail has a label that indicates that it is for RV use specifically.  When I inserted my 1 lb. cylinder adapter into the tank valve and opened it, gas flowed freely.

It is clearly the hose that is the problem, so I will replace it.

Thanks again.

[aw738]

Quote:
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Originally Posted by Jim K in PA
So, I returned here and searched again. Per THIS THREAD I have deduced that my problem is the "leak detector/preventer" in the end of the hose.
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The "leak detector/preventor" is in the tank, not the hose. If you can't get LP through the hose, it is likely clogged.

Note: If you hook the hose to the tank without the regulator and an appliance, it will trip the leak detector, and you will get very little gas through the hose, making it look like it's clogged.

Austin

From:
http://rvbasics.com/techtips/propanevalves.html


The new ACME or QCC valve also contains an OPD (Overfill Protection Device). So you may find them called ACME valves, OPD valves or QCC valves, depending on the supplier. The OPD feature prevents accidental overfill of the cylinder. An internal float mechanism shuts off the valve when the cylinder is 80% filled. The 20% empty space is necessary to prevent the cylinder from venting large amounts of propane when the temperature rises. (ASME type cylinders in most motorhomes have had this OPD feature for many years). The new OPD valve also contains another safety feature - it will not release gas unless the pigtail hose is properly connected, even with the valve open.

This valve would have to have the proper hose assembly attached. Using your adapter that threads into the valve instead of on the outside defeats this safety feature. If your tank will release propane without the adapter than you must have an older tank or a defective valve.

[austinado16]

From:.....This valve would have to have the proper hose assembly attached. Using your adapter that threads into the valve instead of on the outside defeats this safety feature. If your tank will release propane without the adapter than you must have an older tank or a defective valve.

Being the novice/newbie/moron that I am, I've successfully connected the original 1987 propane "inside fitting," regulator and hose of my Starcraft Nova to a brand new 20lb cylinder.  

All my appliances.....carryout stove, fridge, furnace, and catalytic heater all work fine and I've got 11" water column pressure.

[AustinBoston]

From:
http://rvbasics.com/techtips/propanevalves.html


The new ACME or QCC valve also contains an OPD (Overfill Protection Device). So you may find them called ACME valves, OPD valves or QCC valves, depending on the supplier. The OPD feature prevents accidental overfill of the cylinder. An internal float mechanism shuts off the valve when the cylinder is 80% filled. The 20% empty space is necessary to prevent the cylinder from venting large amounts of propane when the temperature rises. (ASME type cylinders in most motorhomes have had this OPD feature for many years). The new OPD valve also contains another safety feature - it will not release gas unless the pigtail hose is properly connected, even with the valve open.

This valve would have to have the proper hose assembly attached. Using your adapter that threads into the valve instead of on the outside defeats this safety feature. If your tank will release propane without the adapter than you must have an older tank or a defective valve.

This is a misinterpretation.  The new valves can accept either an inside or outside thread, alsk known as "new style" or "old style."  The new style wasn't designed specifically to work with the OPD valve, it was designed to eliminate the "left had thread" of the old, inside mechanism.  But there is nothing to prevent using the older mechanism with a new tank.

Austin

[flyfisherman]

My present '99 Starcraft came with a 20# propane tank that has the OPD valve whereas my previous PU, a '96 Coleman/Fleetwood had the older, non-OPD valve tank, which leads me to think that presently I have maybe about the first run of these newer OPD L/P tanks. If that's so, then I experience a little characteristic with the newer tank that I never experienced with the older ones - if I turn the valve on too fast, there will be lock-up with no propane coming out at all, even with a full tank. Maybe certain conditions play a part in this too ... like maybe cooler weather, as the first time it happened I was on a fall fishing trip, way out in the boonies in northern Michigan. My first thoughts were that I had a defective regulator. Lucky for me there was a fellow camper there who put me on to this little OPD quirk.

Immediate action to correct this situation, for my tank anyway, is to shut the tank off and go do something else for a time (maybe 20 minutes?), come back and very slowly turn the tank on. A time or two I even wrapped a rag around the end of a wrench and gave the valve end of the tank a couple of gentle (but firm) raps.  If that really helps I can't be certain ... I just have this "need" to bang on something thats malfunctioning!  Anyway, the point is to turn the tank valve on slowly rather than fast.



Fly

[AustinBoston]

I just have this "need" to bang on something thats malfunctioning!

Wish I could get away with banging on the occasional malfunctioning person I have to deal with.  :yikes:  Might not help, but sure would make me feel better!   :-()

Austin

[PattieAM]

First of all, do you have propane in your 20lb tank?

Open the valve very slowly (if opened fast, it will shut off - safety feature).  Wait a few minutes before lighting your stove burner, and allow time for the air in the lines to escape.  Let the burner burn for a few minutes to allow any trapped air to escape.  Then try your other appliances.

With my Fleetwood Niagara, the water heater takes forever to purge the air out of the line so I can light the pilot.

Best wishes.

[Jim K in PA]

First of all, do you have propane in your 20lb tank?

Open the valve very slowly (if opened fast, it will shut off - safety feature).  Wait a few minutes before lighting your stove burner, and allow time for the air in the lines to escape.  Let the burner burn for a few minutes to allow any trapped air to escape.  Then try your other appliances.

With my Fleetwood Niagara, the water heater takes forever to purge the air out of the line so I can light the pilot.

Best wishes.

Thanks Pattie.  Both tanks I tested with were full.  The final outcome turned out to be a bad hose.  I purchased a new hose and the new one flows fine.

I actually bought two hoses, and an auto-changeover dual inlet regulator, as well as the bracket for dual tanks.  The instruction sheet for the regulator gave a very detailed explanation regarding the type of hose to be used with the regulator.  Short version is that the RV type hose with the green hand connnector is designed specifically for RVs and incorporates a flow sensitive restrictor.  If a sudden, rapid rate of gas flow occurs (like from a failed line, hose, regulator, etc.) a small disk will restrict flow to nearly zero.  As described above, shutting off the tank and allowing the pressure to equalize will normally allow the disk to retract and gas will flow normally when the tank is reopened slowly.

Apparently the flow restriction device in my hose failed closed.

The black handled connector hose is for gas grills, and has a higher flow rate to go with the high Btu rating of those appliances.

The newer OPD valves do not have a leak detection function, but do have another, very important function.  You cannot accidentally (or intentionally) open the valve and cause gas to flow freely from the valve without some kind of device attached to it.  The older style tank valves had no such interlock, and relied solely on the user to insert the little plastic plug into the open valve threads until such time as it got connected to an appliance.  The new design is much safer.

If anyone wants more detailed information from the manual let me know.