Furnace Expansion Tank Full Of Water

The hot water expansion tank is a two gallon tank that hangs off of your hot water system or your boiler.
Furnace expansion tank full of water. Step 2 prepare boiler to drain expansion tank. A description of how the old style expansion tank provides a cushion for expanding water in a hot water boiler system. A hot water expansion tank is a small metal tank usually 2 5 gallons that s installed just downstream of the cold water inlet valve that feeds your residential water heater. Pre charge pressure that s too low may be indicated when the tank is full of water.
This is important because water does not allow the correct pressure for the boiler to work properly. Hot water heating system expansion tank compression tank drain procedure to re charge lost air. If the tank is more than half full of water it is time to purge it. This article describes the steps in draining of a steel compression or expansion tank used on hot water system heating boilers hydronic heat.
The boiler expansion tank absorbs the expanding water by allowing the air in the expansion tank to compress this prevents the pressure. Ratio of air to water inside the steel expansion tank hot water boiler expansion tanks. At least once a year and sometimes twice a year the expansion tank should be drained. You may need to remove air.
Before you turn the power back on and fire up the boiler be sure the boiler is full of water and the heat lines are also full of water. It has an air bleeder on the bottom. The expansion tank s purpose is to protect your house s hot water system from excessive pressure which can cause damage to fixtures your water heater lines and or fittings. Steam boilers are simpler systems that lack several components found in hot water boiler systems such as the circulating pump expansion tank and regulators for water pressure and temperature.
This video is part of the heating and. An expansion tank is not found in steam boiler systems which create heat by circulating hot vapor rather than hot water through the pipes and radiators. Located on the bottom of the expansion tank is a fitting. Tanks not equipped with a site glass need an airtrol fitting.
When water is heated or a hot water faucet is turned off abruptly pressure builds from expanding water molecules. You can also check your expansion tank s pre charge pressure by knocking on the side of the tank with your knuckles to determine if it s full of air or water. Air may also find its way via the heating water to other air bleeders or vents in the system. Low pressure can cause too much water from entering the tank.
In older hot water heating boiler expansion tanks that do not have an internal bladder to keep air and water separate over time air in the expansion tank may become absorbed into the heating water.