2 pressure tanks for well question/problem

Old 04-23-16, 07:30 AM
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2 pressure tanks for well question/problem

My water system consists of a deep well submersible pump that is connected to a 5 gal pressure tank, located approx. 100' from my house.

In my basement the piping connects to a 20 gal. pressure tank.

This system is about 5 years old.

We started losing consistent pressure this week. I checked the tank at the well and the air pressure was only 8-10 pounds. I topped it up to 28 (switch is set to 30-50 lbs.).

This made just a little difference, so I checked the 20 gallon tank in the basement. It showed ZERO at the air valve? I brought it up to 28 pounds, and the water seemed to have better pressure at the taps.

But, now the water in the house has a very bad smell??? The water at the pump house has no smell at all. We have lived here 30 years without any water quality or quantity problems.

Is it possible the smell is coming from the 20 gal. tank somehow?

Was the 20 gallon tank not supposed to show pressure at the air valve? It is a Pro Source Steel tank. I can't imagine there would be anything inside that could be causing the smell.

Old 04-23-16, 08:15 AM
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The pressure tanks only stabilize the pressure so that pump doesn't constantly need to cycle.
Both tanks should have the same pressure in them.

It is possible the water was stagnant in the large tank depending on how it was piped in.

Your pump is what keeps the pressure up. If you are losing pressure you need to determine if the pressure goes down when the pump is not running or if the pump cannot keep up with the demand.

Many times the foot valve in the pump goes bad allowing the water to drain out of the system when the pump stops running.
Old 04-23-16, 09:09 AM
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See if the odor clears after a couple of days. Just messing with the tanks and plumbing can loosen deposits that have built up over time. But if it doesn't clear up pretty quick it should be checked out, especially if the pressure problems continue. In addition to the check valve that Pete mentioned, a leak in the underground water line can also cause pressure issues and water contamination.
Old 04-25-16, 05:56 AM
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Assuming everything is working properly, it is better to leave both pressure tanks on the system.

Two properly working pressure tanks will work the same as one larger tank with the same overall capacity. Each should be pre-pressurized as if the other wasn't there, i.e. to a few PSI less than the pump turn on pressure

Turn off the pump, open a cold water faucet, and wait for the system pressure to go to zero before adding air to a pressure tank. If you know you have a non-bladder tank, then close the faucet before adding air to the tank.

After the pump shuts off both tanks as well as everywhere else in the system should be at the same pressure.

If one tank stays (stayed) at zero that means that the connection to the system is clogged.

Yes, crud could support bacterial growth particularly inside a tank that had its bladder rupture and then had all of its air cushion absorbed by water and then water stagnated inside. With an undersized or no air cushion in the tank, very little water will enter and leave during each pump cycle.


Last edited by AllanJ; 04-25-16 at 06:17 AM.

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