How to Drain an Expansion Tank
- 1). Turn off the electricity or gas running into the heater system. Allow to cool for two to three hours before draining the tank.
- 2). Locate the drain valve. Some tanks need a hose connected to drain the tank properly, while others may require only a large bucket to catch the water directly from the tank. Turn off any boilers, and close the water supply valve.
- 3). Place a large bucket under the drain valve, or attach a hose to the drain valve if there is not enough room for a bucket. Place the other end of the hose in a sink or into a large bucket.
- 4). Open the drain valve. Use a wrench if you cannot open the valve by hand. If the water does not come out, then blow into the hose to force enough air into the tank to cause the water to flow out quickly.
- 5). down a drain or into the yard. Reattach the drain valve, open the water supply and turn on the boilers. Reconnect the electric power or gas.
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