Another plumbing puzzle

[David Meiland]

We periodically get air in our water lines, and I'm trying to come up with a solution. It only happens when my wife runs drip hoses for long periods, and the solution can't be to stop watering, so...

We have a well about 50 feet from the house. There is a 1" line underground into the crawl space to the pressure tank. All of the house plumbing is fed from the tank tee. There is also a tee at the well. The separate shop building is fed from a 1" line underground, pressure provided by the same pressure tank, of course, but one fact being that water moves in both directions through the underground line to the house, depending on where the water is being used.

It is fairly common for my wife to water the orchard from a hose bibb on the shop, while also watering the kitchen garden from a hose bibb on the back of the house. I believe this is the most likely situation that causes the air problem, but I haven't pinned it down--it may also be that only watering the kitchen garden can cause it.

All of this watering of course uses a fair amount of water, so the submersible pump runs fairly often (the pressure tank is 119 gallons and seems to me to give about 35 gallons before calling for a pump cycle).

One possibility that has occurred to me is that the well or pump are somehow introducing the air, but I guess I don't think that's likely. The last time I checked, the pump was 60 feet underwater, and we are in an area with plenty of water and many wells that are 20+ GPM.

Another possibility is that the fact that the water periodically reverses flow direction in a portion of the line is the issue. I'm wondering if this somehow causes air to enter via one or another of the backflow preventers on the hose bibbs.

Any thoughts would be appreciated.

[Marc]

When you checked the water level in the well, was it while the pump was running? Some pumps may have enough GPM to momentarily pull down the water level down.

Marc

[John Kogel]

Does your tank have a 'snifter valve'? It looks like a tire valve and is used to pump air into the pressure tank. Do you ever pump air in?

I had air in my lines sometimes with the last place I had, and I'm pretty sure it was from drawing down the water level in the well. Wives with gardens are hard on well systems. [^]

[Jim Katen]

. . . Another possibility is that the fact that the water periodically reverses flow direction in a portion of the line is the issue. I'm wondering if this somehow causes air to enter via one or another of the backflow preventers on the hose bibbs.

That was my thought as you were describing the problem. You might want to look into a large holding tank near the shop to feed the irrigation line.