Must propane pigtails be identical

[Jackman]

I replaced one of the 12" pigtails with a 20" pigtail and now the generator will only pull propane from the tank connected to the 12" pigtail even with both tanks full. I re-installed the old 12" pigtail and it works as you would expect. I swapped the tanks just to make sure that it wasn't a problem with the tank with the same result.

This isn't a problem for all of the other propane devices, e.g., frig, stove, WH, etc., since these are apparently lower volume devices. So my assumption is that the propane pigtails must be identical for the regulator to work properly.

I'm hoping that the propane gurus on the forum can confirm my thinking or steer me in another direction. And, by the way, the reason I need to replace the pigtail is because the teflon washer that is buried in the green knob is broken and partially missing.

All replies are greatly appreciated.

[Jackman]

red31 wrote:
if green is 400Kbtu, wonder what red is rated?

Red is also 400K. There doesn't seem to be consistency between manufacturers which is perhaps part of the confusion. Or maybe the standards have changed in the last few years.

I studied all the choices at the the RV supplier that I visited to figure it out.
To sum up what I observed:
dark green = 200KBTU/h
lime green = 400KBTU/h
red = 400KBTU/h

[red31]

if green is 400Kbtu, wonder what red is rated?

[Jackman]

Update: The hose (dark green Acme) I installed has a rating of 200KBTU/h. I found the original replacement hose (lime green Acme) which has a rating of 400KBTU/h.

What's sad about this story is that I spoke to the parts guy that sold me the wrong hose and he had no idea they had these ratings.

Lesson learned. All's well and I'm a happy camper again. Thanks for all the assistance.

[wa8yxm]

Generators suck Propane big time, The longer pigtail may be defective or it may be smaller in diameter and the genny can't suck through the small "pipe" as well.

[MudChucker]

pigman1 wrote:
EVERY LP spud on an RV has a flow limiter in it. A spud is the male fitting that goes inside the matching fitting. Each of these has a semi pointed end where the flow limiter is located, even though the outer part of it may have the oversize Acme threaded hand tighten connector. Although they are rated by the number of BTU's they should pass, I've found a number of them that will close at way lower flow rates than they are rated as. My solution is to drill out the spud end and drop the small ball and spring out. No more problems. Although technically you should be able to buy fittings without the flow limiter in the spud, I have not been able find any, so I just use the drill.

We also drill but you cwn fi d the parts you need in a weldimg hose repair kit...

[pigman1]

EVERY LP spud on an RV has a flow limiter in it. A spud is the male fitting that goes inside the matching fitting. Each of these has a semi pointed end where the flow limiter is located, even though the outer part of it may have the oversize Acme threaded hand tighten connector. Although they are rated by the number of BTU's they should pass, I've found a number of them that will close at way lower flow rates than they are rated as. My solution is to drill out the spud end and drop the small ball and spring out. No more problems. Although technically you should be able to buy fittings without the flow limiter in the spud, I have not been able find any, so I just use the drill.

[Jackman]

Thanks for all the replies. To answer some of the questions I installed a longer pigtail because that's all that the shop had. Both are green pigtails (200KBTU/h). I'm suspecting the longer pigtail is defective also. If I buy another I'll certainly buy a pair.

The old 12" pigtail is made by Gas-Flo and the new 20" pigtail is made by Marshal Excelsior #ME518. So I'm definitely working with a mismatched pair of pigtails.

It seems to me that these need to be a matched pair.

[time2roll]

No. The connections can be different lengths without issue. There is something wrong with that pigtail or the way it was installed.

Some trailers have a cylinder on each side from the factory. This makes for a 10' hose on one side.

[Dutch_12078]

Is the pigtail terminated with a POL, or an ACME fitting... ACME fittings are colored to indicate different maximum flow rates. Black fittings are rated at 80,000 BTU/h, green fittings are 200,000 BTU/h rated, and red fittings are 400,000 BTU/h rated. POL fittings are available with or without an excess flow device.

[Isaac-1]

I suspect one of the fittings on the longer pigtail may have an excess flow prevention device in it which is designed to cut off propane flow due to a cut hose, and the generator requires a high enough propane flow vs the stove and fridge to trip the excess flow preventer.

[azrving]

DownTheAvenue wrote:
Perhaps the longer pigtail is defective.

X2
Where did the longer hose come from or who made it? Test the tester.

[DownTheAvenue]

Perhaps the longer pigtail is defective.

[Lwiddis]

"and now the generator will only pull propane from the tank connected to the 12" pigtail"

Another reason I like my manual switch over.

[BFL13]

But why did you swap to a longer pigtail? If longer is needed on that side, then to stay even, can you swap to a longer one on the other side too?