I have two 500 gallon tanks. They have one regulator and propane always ran from what I will call tank two into tank one, if both valves were open. I have been running on tank one and it was down to 15% and I opened tank two and you could hear propane flowing as soon as I opened the valve. I always kept the valve on tank two shut because it would flow into tank one and cause it to release propane at the over flow. I always thought it should equal them out, but it would over fill tank one. I have no idea why but, it must have filled the line between the two tanks and stopped flowing. I was thinking the way it was plumbed it had to go into tank one to get to the house, but after looking at it it can flow from both tanks to to the house. So why would it not fill tank one now, with both valves open when one is at 15% and the other over 80% when it always did before. The T where the two tanks hook is right at the valve for tank one. The valve hooks into the tank one outlet, the T hooks to that valve f, tank two hooks to the T and a pig tail comes out to the regulator. Any idea why it is changed the flow direction? Nothing has changed.

Did the Propane flow freeze up a line?

Is the regulator frozen or maybe going down to 15% might of picked up some water in the tank? Can you loosen the line on the far side of the regulator and see if it’s getting through the regulator?

Propane flows to the house. But it used to always fill tank one from tank two. Now it is not filling tank one, it is just going to the house. I always thought it had too go from tank two into tank one than to the house. That was what it always did if both valves were open. It is bypassing tank one now for some reason. Could it be there is more pressure in tank on and less propane?

Your guage may be broken or stuck on the first tank.

Keith

I don't think it is because I have been watching it pretty close and can see it has dropped looking at it every week. The gauge would not stop propane from flowing into tank one because it does not go through the gauge. When it flows from tank two to tank one you can hear it running. It would run to fill the line between the two tanks and then stop. If I shut tank two off it burns the propane between the two tanks out. Then when it is opened it fills it. It always filled into tank one if both valves were open. The furnace has run three or for time with tank one off and tank two open. It is just acting different than it ever has.

Are the tanks at the same elevation? If one is higher I could see it overfilling the other one. I used to run two tanks and always used one at a time, when one tank was shut I opened the other one. Don’t know why I did it that way, but they would go down equally if both valves were open. Can’t remember how it was plumbed. You could ask your propane supplier.

Do you have a wetline or just moving vapor?

The tanks are end to end about a foot and a half to two foot apart on what I would call flat level ground. Moving vapor. It is just odd to me that it change.

I do not know how it works but I can tell you to give your propane company a call. They should have an service tech on staff .When you get them on the line explain it and they will most likely have an answer without charging you for a service call if you are a regular customer. I would want a system where it would automatically switch from tank one to two at a certain point if that's possible. Running from one tank into another seems odd to me.

It seemed odd to me and I ask the propane tech why it drained from one tank to the other and his answer was he did not know. That some systems did that, and others didn't.

Too many things not adding up, I would get some one to check things out and advise you from there.

Propane goes in the tank as liquid only vapor goes in the reg. And only vapor goes in the house but the vapor can go from the other tank if there is a pressure drop in one tank. Maybe one tank is getting more sun and is warmer. You should hear the flow of the gas at the reg. if the stove is on. Larry