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WATER TANK REPAIR PROCEDURES
AIR DISCHARGE at FAUCETS, FIXTURES
AIR INLET VALVE, WATER TANK
AIR VOLUME CONTROLS, WATER TANK
CONTROLS & SWITCHES on WATER TANKS
INTERMITTENT CYCLING WATER PUMPS
SHORT CYCLING WATER PUMP
SHORT CYCLING CAUSES
SHORT CYCLING CAUSE: WELL PIPE LEAKS
SHORT CYCLING DIAGNOSIS TABLE
WATER TANK AIR, HOW TO ADD
WATER TANK AIR VOLUME CONTROLS
WATER TANK AIR ADD AT AIR VALVE
WATER TANK AIR ADD BY DRAINING
WATER TANK AIR HOW MUCH TO ADD
WATER TANK AIR HOW OFTEN TO ADD
WATER TANK AIR INLET VALVE
WATER TANK AIR LOSS SIGNS
WATER TANK AIR VALVE REPAIRS
WATER TANK AIR VOLUME CONTROLS
WATER TANK BLADDERS & CAPTIVE AIR
WATER TANK BLADDER PRESSURE ADJUSTMENT
WATER TANK DRAIN VALVE
WATER TANK LIFE EXPECTANCY
WATER TANK PRESSURE CALCULATIONS
WATER TANK PRESSURE GAUGE
WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER TANK REPLACEMENT
WATER TANK SAFETY
WATER TANK SIZE & VOLUME
WATER TANK REPLACEMENT
Air volume control elimination: this article explains how to get rid of the AVC or air volume control entirely. AVCs are required to maintain the air charge in a water pressure tank that does not use an internal bladder. By changing the water tank itself we can eliminate this control and its occasional issues. But there are some things to watch out for, such as leaving old AVC controls in place (a snifter valve in the well?) where they no longer belong.
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If you convert from a non-bladder type water pressure tank to a water tank using an internal bladder, part of that installation will include the removal of any air volume control valves on the system, including an AVC that may be mounted on the well pump (above-ground jet pumps) or a hidden AVC that is found inside the well piping (submersible well pumps only).
Remove and Discard the Air Volume Control Valve
You can keep the older bladderless water pressure tank and still remove the AVC entirely, abandoning its automatic function, but if you continue to use a bladderless water pressure tank you will need to restore air into the tank from time to time using one of the other methods discussed in this article series: WATER TANK AIR, HOW TO ADD
If the the rusty, leaky air volume control valve does not work, can I just remove it?
The short answer is sure. Or if it's not leaking you can leave it in place, which is safer as it avoids disassembly and possible trouble sealing the fittings against water leaks. But if you abandon the air volume control you will occasional have to add air to the water pressure tank (WATER TANK AIR, HOW TO ADD) when the well pump starts to short cycle (SHORT CYCLING WATER PUMP) or turn on and off too often.
In 40 years of messing with plumbing I've rarely found an old AVC that worked reliably for long in a residential application. The AVC at left (that round thing in the center of the photo) was found by Langdon who found it to be rusty, leaking, and not working. He replaced it.
An air volume control on a water pressure tank can be left in place but don't count on it to work. If the air volume control valve itself is leaking or fittings on its tubing leak, you may decide, as do many plumbers, to simply remove it.
Just screw in a pipe plug where it was mounted on the water tank, and a smaller (usually brass) plug may be needed at the point of connection of the other end of the copper tube if one was installed on your system.
(You'll have to turn off the pump and release water pressure and drain some water from the tank before replacing an AVC with a new one or with a pipe plug.)
In rare cases an air volume control may put too much air into a pressure tank - see AIR DISCHARGE at FAUCETS, FIXTURES.
If your AVC is not working or has been removed, and if your water tank is a non-bladder type system, you'll need to use
one of the other methods discussed here for adding air to your water tank when it's needed. Forget this method for maintaining the proper air charge in a water tank, except for the Leaky Air Volume Control tip below.
Remove old Air Volume Controls if Changing to an Internal Bladder Water Pressure Tank
Those controls will inject air into the water (that is inside the bladder) duplicating the role of the bladderless tank whose air charge is kept separate from the water in the tank. A result of leaving old AVC components in place might be less water draw-down before the well pump has to run and also air discharge at faucets.
Look for and remove the following, not all of which may be present on your system:
Continue reading at WATER TANK REPLACEMENT or select a topic from the More Reading links shown below.
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