Propane frustration

[Barefoot Bill]

Can't get propane to flow from tank on opposite side from the main valve (pressure regulator/changeover valve). Have replaced pigtail, pressure reducer (was 15psi, new one is 20psi) and the main valve. All that remains is the pipe that crosses over and hose between that and main valve. Blew compressed air through them and DW said air was coming out of the other end.
But propane still won't flow even when switched manually much less automatically. Any ideas? Is the air that got in the system while replacing parts a problem?

I've considered removing the pressure reducer. I assume the reason for that is so that full tank pressure isn't going all the way across in case of rupture during a crash. We always turn off both tanks when the trailer is on the highway so I don't see a hazard there. However, I don't know if this would solve the problem.

Getting tired of carrying tanks from one side to the other when they need to be switched. Note: This may have been a problem ever since we bought this 2010 3400RL last summer or may have started later. I don't remember.

[davemitchell59]

Have you tested your regulator? It sounds like your tanks work fine if you're able to use both tanks on one side. Seems like your regulator isn't accepting inflow from the far side.

[b.o.plenty]

It's not a pressure reducer it's a regulator. It maintains a constant even pressure to your appliances. If it was set at 15 PSI that's what it should be not 20. If the 20 PSI regulator didn't change anything that wasn't the problem anyway. It is not designed to shut the flow off if a line ruptures. If you turn the tank valves open too fast they will shut off the flow. It sounds like you need to hire a professional to look at this before you blow something up.

[mlh]

Take the tank out and bounce it around a little bit. Put it bank in and open the valve VERY SLOW. The shut off might be closed this will allow to to open.
Lynwood

[BB_TX]

I don’t remember anyone saying their high pressure propane regulator was 15# or 20#. Every post I remember stated theirs was 30#. I know mine is 30#. And is even stated as such by the NFPA standard that requires it. You can read an earlier discussion at the link below. Don’t know that the lower pressure would affect the 2 stage regulator though.

Regulator valve discussion

[Twopetes]

I had to replace the regulator on my HC and it was 12-15 PSI. The original regulator was 15 PSI.

[Barefoot Bill]

Thanks for the responses. I started out with the"professionals". I assumed the problem was the far side regulator. They replaced the original 15 psi with a 30 psi and replaced the pigtail, had me turn on the stove.and when it lit, they said problem fixed. After they left, we discovered that the stove would only stay on for 5 sec. or so but then go off. The "professionals" came back for something else and I told them the problem wasn't fixed. I don't think they replaced anything but said it wouldn't switch over automatically but would manually. After they left, we found no improvement.

So I decided to take matters into my own hands. I was concerned about the 30 vs 15 psi regulator, so I went to the store, got a 20 and another pigtail and installed them. No change. Thought well it must be the main valve/2stage regulator, so I bought a new one and installed that. No change. Then I blew air through the crosspipe. No change.

Both tanks work on the near side, and both were just recertified and received new valves. I'll try bumping the tank around and opening the valve slowly. As far as testing the new main regulator, I guess I could disconnect the hose from the far side and connect the near side tank to that side of the regulator to see if that works.

Alternatively, I'll be having an awning installed at CW in a couple weeks and I can see if they can do better than the other bozos.

But I have a question. Why does the far side need the extra 15/20/30 psi regulator while the near side doesn't when both go through the same 2-stage regulator, which is really what regulates the pressure to the appliances??

[Barefoot Bill]

I just read the link BB_TX gave. That confirms my assumption that the extra valve is safety related. It says 30 psi or less. Thanks.

[rohrmann]

The main reason for the red regulator is to make sure that once the propane leaves the tank as a vapor that it stays a vapor. Propane regulators in trailers do not regulate liquid only vapor. If the regulator was not there the pressure in the hose/pipe would be the same as the tank. This could lead to the vapor condensing back into a liquid. With a reduction in the pressure from the regulator to the other side of the coach this will greatly reduce the possibility of the vapor in the crossover hose/pipe turning back into a liquid. This is all based on propane’s vapor/pressure saturation points. The lower the pressure the lower the temperature to turn it back into a liquid.


It really sounds like you have a problem with your auto changeover regulator not switching. They really aren't that expensive to replace and that seems to be the only thing that you haven't replaced. They do fail, and last year, I replaced the one on my father-in-law's TT that was less than two years old. This is the one I replaced on our Montana earlier last year. https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I did not need the bracket that they show with it, as the existing bracket that was on the old regulator transferred over as an exact replacement. Also, the new regulator was pre-adjusted, so did not need to do anything to it beyond just replacing it.

[Barefoot Bill]

Thanks for the explanation, Rohrmann. I did replace the changeover valve/regulator with a Marshall Excelsior.

That's what's so frustrating. Everything is new except the crossover pipe and it's downstream hose. Unless one of the new components is defective, I can't think what else the problem can be.

I will try the advice about opening the tank valve slowly, but both tanks work fine without doing that on the main regulator side. I'll try that tomorrow.

[twindman]

I just had an idea. Swap the hoses on the regulator so the pig tail from the driver's tank now goes into the previous crossover input. This would tell you whether the regulator is bad or not. If this works, then it is in one of the crossover pigtails or the pipe itself.

[waynemoore]

I have never had the cross over work on any of the 3 rigs I have owned. On the first one it made me crazy trying to get it to work. Spent lots of money and time with no fix.

Then one day I broke the code. Decided life was far too short and just decided to keep moving the tanks back and forth.

Yes I know it is supposed to work but it just won’t.

Now I am happy, it is just one of the things I do when it needs doing.

[rohrmann]

I had an excess flow valve stuck closed in one of the pigtails several years ago. This is the valve that is inside where the plastic nut is on the pigtail. I replaced both pigtails and was back in business. Another benefit of replacing both was, the old ones were very stiff and were likely to break if I attempted to straighten them. We have been full time since 2012, and use the propane like the system is designed and have never had the change over valve not work. The only reason I replaced ours was because the red/green indicator stopped working.

[Barefoot Bill]

Disheartening input from waynemoore. There must be a fix. The stuck valve in the pigtail makes sense although mine is new. Tomorrow, I think I will see what I can do. Maybe tapping here and there to free up stuck valves, etc.

[Jeffrey]

Don't give up, you laugh when you fine what the problem is. With all the info that has been mentioned it has to be one, there is nothing else there!

[Barefoot Bill]

I was looking at the Trekwood parts for 2010 Montana and they have this changeover/regulator kit. Wondering if this would work better than the items I have installed.
https://www.trekwood.com/products/14...ets-Right-Side
They also have 30psi regulator for other side (rather than 15 or 20)
I think I'll wait and see if the techs at CW can do anything since I'm taking the trailer there anyway next week.

[Barefoot Bill]

Problem solved. Had the trailer at CW in Idaho Falls yesterday for awning fabric replacement and a few other things. They bench tested the main regulator and found that it wasn't allowing flow from left inlet. That was a new Marshal Excelsior regulator that I installed a couple months ago.
I was impressed by the customer service and professionalism at this CW. And they finished by the end of the day as they said they would. Best I've experienced at a repair facility in 12 years of RVing.