The Pressure Tank
The pressure tank serves two-purposes, holding water in reserve and controlling the dreaded water hammer. The size of the water pressure tank dictates the amount of water reserve and the draw down time of the pumping cycle. The air column inside the pressure tank, whether it is a bladder or bladderless, keeps the water pump from "hammering" the plumbing pipes. Hammering is easy to detect as the entire system will severely shudder when the pump comes on and shuts off. If your well system begins to water hammer; shut the system off immediately as damage may occur to the plumbing pipe joints and faucet valves. Pump short cycling is another indication of losing the air column. Short cycling is just as it sounds; the pump turns on and off many times in one- minute when water is being drawn from the system.
Water hammer is caused by a lack of air inside in the pressure tank. The amount of air inside a bladder type pressure tank is easily checked using a regular tire pressure gauge. Shut off the electrical power to the pump. Open a nearby water faucet and drain the system of all built-up water pressure.
Locate the air filling valve on the bladder type tank. The air valve looks just like the one on your vehicle or bicycle. Pull the plastic cap from the valve and press the tire gauge to the valve stem. Read the interior bladder pressure. The gauge should read 2 pounds per square inch (PSI) less than the cut-on pressure of the system. In most all cases, the bladder should contain 28-PSI of air pressure for a 30-PSI water system.
Add air to the bladder using a bicycle hand pump or an external compressed air source. DO NOT ADD EXCESSIVE AIR PRESSURE AS THE AIR BLADDER WILL RUPTURE! Remove high air pressure by pressing the small needle valve in the center of the stem with your fingernail.
Bladderless tanks are even easier for adding air to the system. Shut off the electrical power and drain all water from the tank. Leave the drain valve open at the base of the tank for a few minutes. Close the drain valve, re-apply electrical power. Allow the water pressure to build. The air captured inside the bladderless tank will automatically create the cushion required for regulation.
A leak in the top of a bladderless tank will cause the air column to escape and fail. Small leaks are often indicated by wet rust marks at the top half of the tank. Replace the tank instead of trying to fix it with some J-B Weld. Over time the patch will fail.
Water logged bladder tanks indicate a rupture to the rubber membrane, indicated by excessive water hammer and pump short cycling. Water logged bladders will show themselves after several attempts of adding air to the rubber membrane fails. Some bladder tanks are serviceable, most are not. Serviceable bladder tanks have a large access port on the bottom of the vessel.
