Detailed specs about replacement propane hoses

[Jeff the marmot]

I now understand that a previous owner of my 2009 2720SD (with the horizontal propane tanks) replaced the propane hoses and didn't buy the right thing. So the hoses I have are somewhat too long (24") and have a mystery kludge adapter on the ends of both hoses.

One of them seems to be leaking and I would like to get the right replacement hoses for both tanks.

It looks like about 18" or maybe 20" length would be about right. Should the small fitting be 1/4" male NPT or is it 1/4" male inverted flare? I see that both of those fittings are common. That's apparently the mistake that the previous owner made with mine. The other end looks obvious to be the Type 1 ACME fitting.

I see an aweful lot of bad reviews on-line about Chinese rubber hoses only lasting a year or less before they leak. I don't mine spending more for good quality products but I need to know the specs. Camco looks like they are probably Chinese-made and there are a lot of bad reviews about them, so I don't want to go that route. Does anyone have stainless braided hoses? Usually the inner layer is a good quality rubber and the braids are just the outer layer for protection and help with holding the high pressure and also to keep UV off of the rubber. Any reason to not go with stainless braided hoses on a trailer? Thanks for any thoughts about upgrading the hoses.

Edit: I'm now thinking this is 1/4" NPT at the regulator because both the hose end and regulator fittings are perpendicular and the threads have a slight taper. I think this is the original regulator based on how aged it looks for a 9 year old trailer. I think NPT threads also mean thread tape is essential, right?

[Kidkraz]

I replaced both of my hoses with these from Amazon in early 2016 and I've not had any problems with them. I was able to choose the lengths of the hose I needed. The other item is to make sure you have a green nut on the end that attaches to the tanks. Getting the wrong version of hose is a problem

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1


http://www.trailmanorowners.com/foru...n+propane+hose

[Jeff the marmot]

Thank you for the input. That link has valuable info about the Type 1 fitting rating and color. Definitely green on that end then.

It's interesting that the fitting at your regulator end is the 1/4" inverted male flare, not NPT.

Any differing opinions out there? Did TM change the regulator type and fittings at some point?

[Bill]

Although I know they exist, I've never seen a green knob/nut. All TMs that I have ever seen were factory-equipped with black nut connectors, so that would seen adequate according to the factory. I do see in Dave's thread, linked above, that some TMs had green, so I conclude that the distinction is not real important. TM often used whatever parts they could get most quickly or cheaply at the moment.

According to the "Expert Answer" at e-Trailer (often a better source of info than Amazon, by the way), the only difference between a black knob/nut and a green one is that the black one can provide gas flow to support 70,000 BTU/hour of appliances, while the green one can provide 200,000 BTU/hr. Given that the biggest user in a TM is the furnace, which is rated at 17,000 BTU/hour (or 20,000 in more recent years), I'm not sure that the entire TM could demand 70,000 BTU/hr. I suppose it is possible that if every gas appliance fired up at the same moment, the total might approach 70,000, but at the moment, I don't have access to my blue book to check.

As for the other end of the hose, why not read the manufacturer's name and model number on the regulator, then check its on-line specs to see what kind of fitting it needs.

Bill

[Jeff the marmot]

Thanks for the guidance, Bill!

Originally Posted by Bill

As for the other end of the hose, why not read the manufacturer's name and model number on the regulator, then check its on-line specs to see what kind of fitting it needs.

What a great idea.

The regulator on my TM is from Marshall Gas Controls in San Marcos, TX. I had to unscrew it and look on the back to see the model # 250.
Marshall Gas Controls apparently used to have a web site at www.marshallgas.com but that domain name no longer exists and is for sale. Their customer service 1-800 number has been re-allocated to a satellite TV service. So dead end there.

There's some general info about the Marshall Gas Controls company here:
http://www.lpgasmagazine.com/lp-gas-...-gas-controls/

Marshall Gas Controls Model 250 was known to be manufactured in 1994 and was recalled in 1995 due to problems with leaking propane. Recall web page here:
https://www.cpsc.gov/Recalls/1995/cp...gulator-recall
That web page also says that the company went out of business.
I wonder how that part got on my 2009 TM. I just lost some respect for the previous owner of my TM.

That solves my problem, though -- I need to replace my ancient not-to-be-trusted regulator with a new one with known fittings. Then I can match new hoses to it.

Oh, and for anyone curious about whether thread tape is needed - I did see that NPT threads are designed for use with some sort of tape or thread sealant. Yellow tape is intended for gas, so don't use the white tape. That's only for NPT threads, though, not the inverted male flare....

[eddugo]

I had propane leaks on my '09 (horizontal tanks) and changed the hoses and still had leaks. It was the valves on the tanks - just would not seal. The rubber ring in the valve is not replaceable - had to change the valves.

[Bill]

Good sleuthing, Jeff. I had forgotten that the original Marshall Gas had undergone major changes several years ago. I seem to recall that it had split into two companies (Marshall Gas Controls and Marshall Excelsior maybe? Somehow the name Leggitt was also in the mix), one aimed at industrial customers and one aimed at consumers, including RVs. I also recall that neither one had a particularly easy-to-navigate web site. I'm glad you were able to find what you need.

Like EdDugo, I began searching for Marshall stuff when I began to sniff propane in the trailer tongue area. I finally used the soapy water solution to trace it to the handwheel valve on one of my horizontal tanks. The valve would shut off nicely when the handwheel was cranked down, but would begin to leak slightly as soon as the valve was opened a bit. I tried putting a wrench on the valve body, but no go. I ended up with the same solution you did - new valve. Kinda spendy, as they say, but you gotta do it.

Bill

[eddugo]

I got a great deal on the valves by the local gas company - affiliated with Amerigas. They charged me $32.00 for both valves. i am a steady customer so they just charged parts only.