Waterlogged well pressure tank: cost and asking a seller

What does it mean when a pressure tank is waterlogged?

A waterlogged well pressure tank is full of water with no air cushion left. On a typical home bladder tank, that means the rubber bladder inside has torn, and it can't be repaired. The fix is a new tank. Ask the seller to replace it before closing, or to credit you the cost from a well contractor's written bid. Do it now, because the tank is also wearing out the well pump.

Key takeaways

• Sources put a tank-only replacement at $600 to $1,800 installed. The pump figure applies only if the contractor finds the pump failing too: $2,500 to $5,000 or more with the tank.
• The conclusive test is at the tank's air valve: if water comes out instead of air, the bladder has torn.
• Adding air is not a fix for a torn bladder. Ask for a replacement, not a recharge.

How much does it cost to replace a well pressure tank?

Kept prices every line of an inspection report for $79, usually under 4 hours, and marks the ones that need a professional quote.

Tank size moves the number most. A crawl space, or a tank that has to come up stairs, pushes the labor toward the top.

What happens if a pressure tank is full of water?

The tank stops storing pressure, so the pump does all the work. National Water Service, a well contractor serving the DC area, says: every time you open a faucet, the pressure drops and the pump turns on. That constant starting and stopping overheats the pump motor and can burn it out.

Mid Atlantic Water, a well-equipment retailer, says pump makers rate submersible pumps for roughly 6 to 8 starts an hour, and a waterlogged tank can push that past 100. Catch it at the tank and you buy a tank. Miss it and you may buy a pump too.

Under InterNACHI's well inspection standard, an inspector must report "any waterlogged well pressure tank" as in need of correction. It is a defect, not a maintenance note.

How do you tell if a pressure tank is waterlogged?

A common sign is short cycling: the pump clicks on and off every 10 to 30 seconds while water runs. Faucets may spit or pulse when the pump kicks on.

One quick check points the same way, and the well contractor can do it. Knock on the tank near the top and near the bottom. A healthy tank sounds hollow on top; a waterlogged one sounds dull and full at both spots.

The conclusive check is at the air valve on top, which looks like a tire valve. With the pump off and the tank drained, a gauge pressed on the valve should release air. Water means the bladder has torn. Leave this one to the well contractor: the pressure switch next to the tank is live.

How do you fix a waterlogged well pressure tank?

It depends on the tank:

• A bladder tank has a tire-style air valve on top. The bladder is sealed inside the shell at the factory, so the fix is a new tank.
• An old galvanized tank has no bladder, so air and water share one chamber. Draining it and letting it refill restores the air pocket for a few months. When it needs draining more than every couple of months, replace it with a bladder tank.

Replace the pressure switch and gauge with the tank. They are the same age as the tank, and a switch on a short-cycling tank has taken thousands of extra hits.

What should you ask the seller for?

Have a well or pump contractor confirm the tank is waterlogged, check the pump, and give you a written bid. How to get repair estimates during the inspection period covers getting one fast. Then ask for one of two things:

• Replacement before closing: a new tank, pressure switch and gauge, installed by a well or pump contractor, with a paid invoice.
• A credit equal to the contractor's written bid, if you'd rather hire your own.

Ask the contractor to measure the pump's output against its nameplate. If the pump is failing too, your ask moves to the tank-and-pump row above. What to ask for after a home inspection shows how this line sits with the rest of your list, and the buyer repair request letter template covers the wording.

What if the seller says no?

A tank alone is a bounded cost with a clear fix, so put the bid figure into your overall credit or price ask. If the seller refuses everything, budget the replacement for your first weeks in the house, because the pump keeps wearing until it's done.

If the contractor finds the pump failing too, the number is bigger. Weigh it with when to walk away after a home inspection. Your contract sets the deadline for the request, so confirm the date with your agent or attorney.

Can the seller just add air to the tank?

Only if the bladder is intact, and even then it is a stopgap. A tank that has simply lost its air charge can sometimes be recharged, but that is usually a sign failure is coming soon. You can't check or set the air charge without draining: it is set with the pump off and the tank drained, and under pressure the gauge reads water pressure instead. If the charge is low again within a week, the bladder has a pinhole.

Mid Atlantic Water also notes that Amtrol's own manual says not to add air to a tank that has already lost its charge. Ask for the contractor's air-valve result in writing before you accept a recharge instead of a new tank.

How long does a well pressure tank last?

Mid Atlantic Water calls 10 to 15 years typical for a quality bladder tank. Acidic water, heavy sediment or a badly sized tank that cycles constantly shortens that. The same retailer says to replace a tank over 15 years old that shows any symptom. On a tank with no symptoms, ask the well contractor how old it is and to check the air charge.

If the tank is one finding among many, upload your inspection report to Kept and spend your remaining days on the well contractor's bid.

Sources

• InterNACHI Well Inspection Standards of Practice
• National Water Service, Signs of Well Pump Failure vs. Bad Pressure Tank
• Mid Atlantic Water, Well Pressure Tank Troubleshooting
• Mid Atlantic Water, How Much Does a Well Water Pressure Tank Cost?
• The Well Guide, Pressure Tank Replacement Cost