A pressure tank needs replacing when water comes out of its air valve, when it shows rust or seepage, or when it keeps losing its air and the pump starts every few seconds. At that stage, the tank should not be re-inflated; it should be replaced. At Wilfrid David in Chénéville, we replace well pressure tanks throughout La Petite-Nation. Here are the signs we look for.
The pump starts too often
This is almost always the first sign. The tank has lost its air cushion, it fills within seconds, and the pump restarts as soon as a tap is opened. On the gauge, the needle rises and falls rapidly. Other components, such as the pressure switch or the check valve, can cause the same symptom; all the causes are covered in our article on a pump that keeps cycling. When the tank is the cause, it should be addressed quickly, since every start wears the pump.
Water at the air valve
The top of the tank has a small valve, similar to a tire valve. Normally, air comes out when you press it. If water comes out instead, the diaphragm or bladder that separates the water from the air is torn, and water has taken the place of the air.
One tank manufacturer uses this test to confirm a leaking water cell. On some models, the cell can be replaced; on many others, the entire tank must be. In either case, adding air will not provide a lasting result.
Rust and seepage
Examine the bottom of the tank, the seams and the fitting. Rust that makes the paint bubble, water marks on the floor or an orange ring around the base indicate that the steel is deteriorating. A major manufacturer's manual is clear: the precharge on a tank with visible corrosion should not be adjusted.
A well tank is under pressure at all times. A small rust spot may seem minor, but it can lead to a leak, sometimes onto a finished basement floor or in a cottage that is unoccupied. It is best to have the tank checked as soon as these signs appear.
A tank that keeps losing its air
If air was added in the spring and the pump is cycling again by the fall, this is a sign of wear, even if nothing is visible on the outside.
The same manufacturer warns that a tank that has lost air, or whose pump cycles faster than when it was installed, may have internal corrosion. Re-pressurizing it can make it burst and cause serious injury. The manufacturer also states that only qualified professionals should check or adjust the precharge. For this reason, we advise against using a compressor to re-inflate a tank that has lost its air.
What a replacement involves
Replacing a tank involves more than removing the old one and installing a new one. The tank must be sized for the pump and the needs of the building. The precharge is set 2 psi below the pressure switch cut-in (28 psi on a 30/50 setting, 38 psi on a 40/60 setting), with the tank empty. We also check the surrounding components, such as the pressure switch, the gauge and the fittings, which are often the same age as the tank. The same manual also calls for a relief valve in case the pressure switch fails to shut off the pump.
For cottage owners, the manual notes that bacteria can grow in a tank, particularly when it goes unused for some time. After a replacement, or when reopening after several months away, a water test is recommended. The Government of Québec also recommends testing water from a private well for bacteria at least twice a year.
Finally, the manufacturer recommends that a professional inspect the entire system every year, and more often as it ages. For a cottage, the start of the season is a good time for this inspection.
When to call a professional
Water at the air valve, rust or a leak at the base, a tank that keeps losing its air, or a pump that starts every few seconds: call us at 819-428-3161. We confirm whether the tank is the cause, replace it if needed and set the precharge to match the pressure switch. If you have no water at all, start with what to check when there is no water. We are located at 77 rue Principale in Chénéville. Evenings and weekends, emergencies are handled on call. For more information, see our wells and pumps page.
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