Expansion Tanks: Water Heaters
Water heater expansion tanks are designed to provide additional water capacity needed due to thermal expansion as heated water enters the tank through incoming pipes. Thermal expansion occurs when heated fluid increases in volume as it becomes hotter. Expansion Tanks also help prevent pipe damage due to Fluid hammer, which is produced during fast shut-off situations (i.e., faucet or appliance shut-off). Without an Expansion Tank, the excessive force would be exerted on shut-off valves and piping. Expansion tanks also help protect appliances and fixtures by alleviating pressure caused by high-velocity flow where supply pipes become too rigid for the flow of water. Expansion Tanks are required in some areas as life safety protection.
Expansion Tank Facts:
- Expansion Tanks require no maintenance.
- Expansion Tanks do not need to be upgraded for life safety protection.
- Expansion Tanks are required by code in some areas unless a licensed plumber, engineer, or architect certifies that installation of an Expansion Tank is not needed