Problem with Propane Regulator(s)

[CarnationSailor]

I have dual 30-lb tanks and an AUTO-CHANGEOVER TWO STAGE PROPANE REGULATOR (similar to model #6020/F273766 made by Enerco). My Tank #1 is directly connected to the auto-changeover regulator, and Tank #2's output goes thru another propane regulator before connecting to the auto-changeover regulator. (Tank #2 is on the other side of the trailer from the auto-changeover regulator.)

In May of this year, #2's regulator began leaking thru its vent port, and I replaced it.

Last week I needed to refill the #1 tank so I pointed the switch on the auto-changeover reg. to the #2 tank. I also shut off the #1 tank and disconnected the pig tail. As soon as I disconnected the pigtail, gas leaked from it. I have since found that this is normal as I need to cap off the pigtail or shutoff the other tank too, which I did.

When I returned with a full #1 tank, I hooked it up and opened the tank valve. Gas immediately started flowing at a large rate from the vent on the #2 tank's regulator. The gas stopped flowing when I pointed the switch back to the #1 tank.

So here's what I know:

Both tanks are full.

Either tank will provide gas without any leaking if I select it and open only that tank's valve. However, the red flag on the auto-changeover reg. will only go away if the #1 tank is selected. (The red flag is supposed to indicate an empty tank.) Gas flows OK from the #2 tank - it's just that the red flag incorrectly indicates an empty tank.

With #2 tank selected and only its valve open, there are no leaks. If I then open the valve on the #1 tank, gas flows (leaks) from the #2 tank's regulator vent.

I think the fact that gas is flowing from the vent on the #2 tank's reg. under any circumstances indicates a bad regulator (again). I have a new one on order.

But what about the auto-changeover reg.? Do any of the symptoms indicate that it may also be bad?

Final question:

Assuming that the auto-changeover reg. is intended to have two tanks directly connected to it, why is there a separate regulator on the (remotely located) Tank #2? Is this because the propane line runs thru the interior of the trailer to get to the auto-changeover reg, and they only want low pressure gas routed thru the trailer (for safety reasons)?

[wa8yxm]

Your problem is the change over valve. It is not working properly.

This valve is supposed to prevent check vlaves so insure gas can not travel tank to tank. The pre-regulator on the #2 tank when it sensed gas at HIGHER than preset pressure (coming from Tank 1) Vented as it is designed to do.

[time2roll]

Recent thread in Fifth Wheels

[Chris_Bryant]

First answer and it is succinct and correct. Sheesh, where's the fun in that.

As to the other question, I suspect the auto changeover is fine, the bad high pressure regulator could cause all of the symptoms.

[time2roll]

CarnationSailor wrote:
Final question:

Assuming that the auto-changeover reg. is intended to have two tanks directly connected to it, why is there a separate regulator on the (remotely located) Tank #2? Is this because the propane line runs thru the interior of the trailer to get to the auto-changeover reg, and they only want low pressure gas routed thru the trailer (for safety reasons)?

Required by code any connection longer than 60 inches must have a regulator to reduce pressure and prevent condensation in the line.