I am having trouble with the flow from the right hand side propane tank in my fifth wheel. (This is when the left tank is empty.)Everything will work off of the right tank except the furnace. When the furnace comes on the system shuts down as if the tank were empty. I can shut down the furnace, wait for system pressure to build up and everything will work, except the furnace.The system has a small red regulator on the right tank side and I know the tank pigtails have some type of leak restriction built in. So my question is what is the likely culprit, the pigtail of the little regulator?Obviously I have no idea why the system has the little red extra regulator.

I had the same problem with mine Pete, I have two 40 gallon propane tanks, you can switch sides just like yours, my selector switch/regulator is located on the drivers side(Left side) of the 5er, the other tank located on the curb side, (right side) also has a red regulator....When I turned the furnace on, using the left side propane tank, there wasn't enough pressure to keep it lit, though it would have enough to cook with, to run hot water heater and to run the refrigerator. I checked hoses for obstructions, found none..replaced the red regulator on the side that couldn't keep the furnace lit....it didn't help..SOOOO, I replaced the regulator on the other where you select what tank you want to use, and BINGO...problem solved :).....Ever since I replaced the combination selector valve/regulator on the drivers side of the 5er, either tank will now keep the furnace going. That was my experience...

RED regulator on off side cylinder is a single stage 30# regulator.........they have been an issue.They reduce cylinder pressure down to 30# before feeding it across to main 2 stage regulator. Pigtails have a excess flow check valve---ball bearing style that closes off if pressure on both sides of ball are not equal.They have been an issue with gumming up and sticking close.Main 2 stage regulator takes cylinder/high line pressure and reduces it to 0.4 psi (11" WC) to feed propane system.There have been issues with them.Which one is causing your problem.......Hard to tell via internet.You need to swap cylinders around, try different set ups to eliminate issueOR throw parts at it.......RED regulator first.

I was going by my own personal experience with what seems to me to be the exact same problem as the OP's, less than a year ago....I swapped tanks, checked hoses, and then next step, to me was to replace the regulator on the side that wasn't allowing furnace to stay lit. .I then did what Old Biscuit suggested, replaced the "red" regulator...didn't make any difference, in my case, still had the issue, but doesn't mean it won't solve your problem, was just my first "replacement" of components in my trouble shooting steps. But, .furnace wouldn't stay on...Next, and only component that I had not checked was the selector/regulator on the drivers side of my 5er...I replaced the assembly and it immediately resolved my problem..Thus the reason I posted my opinion..Guess it could be wrong, but sounds like identical problem and a possible solution to his problem...it worked for me.

That's why one needs to try different set ups........otherwise you just start throwing parts at it

Restricted propane Flow | Good Sam Community

TubaPete
Explorer
Jan 23, 2015
Just so everyone knows, I found the problem.

By switching leads into the cross over regulator, I figured the problem was somewhere in the feed from the right tank. After "throwing some parts at the problem," I found the crossover pipe has a small adapter / check valve leading into the main regulator. It was partially blocked.

Everything works now. Thanks for the help.
GASMAN6674
Explorer
Jan 14, 2015
Just FYI
The red regulators in these systems is there to keep the vapor from re-liquefying in the longer hose. Its a safety issue but a real PIA.
kirbybear
Explorer
Jan 14, 2015
Just had the same problem. The pig tail from the right tank orifice was about 1/64" in diameter. The left side was about 3/16". Drilled out the orifice to same size as left tank.
NC_Hauler
Explorer
Jan 14, 2015
laknox wrote:
This is why I prefer trailers with the tanks on the same side. :-)

Lyle

That does seem like a better set up...I also like a set up where they set on a platform and you can slide out unit, makes it much easier to get out to refill and easier to put back in place.
laknox
Nomad
Jan 14, 2015
This is why I prefer trailers with the tanks on the same side. :-)

Lyle
wvcampers
Explorer
Jan 14, 2015
I also took the red regulator off, but I replaced the crossover rubber hose with hard pipe. The red regulator is there to protect the rubber hose that is running to the other side of the camper. I had 2 of the red regulators fail. They both started leaking.
timflood
Explorer
Jan 14, 2015
Well, I took my red regulator of and put in the trash. I went 6 years without one.I had 2 of them go bad on me. The second time it went bad I made the mistake of running out of propane. That's what I did, I am not telling you to do that, just what I did
NC_Hauler
Explorer
Jan 13, 2015
Exactly, everything I covered in my first post...forgive me if I took your post the wrong way. I really am "at ease" though:)
Old-Biscuit
Explorer III
Jan 13, 2015
NC Hauler wrote:
Old-Biscuit wrote:
That's why one needs to try different set ups........otherwise you just start throwing parts at it

I'm not disagreeing with you, you and I are in agreement, nor did I "just throw parts at it"...I did as I stated in the first response to the OP's question in this thread , I checked tanks and hosing first, swapped tanks around etc...when nothing worked, I next replaced the red regulator...when that didn't work, I replaced the selector switch/regulator...that fixed it.

I took steps, why would you suggest I didn't and that I "just threw parts at it"? That's the way I took your post.

My suggestion was literally identical to your's...

Ease up..........

Wasn't calling you out or anything close to criticizing.

OP needs to go thru steps to eliminate what could be causing issue.
Something none of us via Internet can do for him.
Three things could cause his problem
Red regulator, crossover hose or 2 stage main reg.

Plain and simple..he has to try swapping things around OR throw parts at it.
NC_Hauler
Explorer
Jan 13, 2015
Bob Quinn wrote:
What Old Biscuit said, I;ve had it happen (Red Regulator is most lickly bad)
Bob

Again, as "I" stated in first post...just so happens with mine, though I took the approach that it "had" to be the red regulator, in reality, it was the other regulator/tank selector set up. I think easiest to change first, if it comes to that would be the red regulator...other one was a little harder to work with. It's really an easy trouble shooting process.