Water Heater Thermal Expansion Tank Required

When water is heated inside your water heater it expands.

Water heater thermal expansion tank required.

The water heater expansion tank serves as an overflow receptacle by absorbing excess water volume that occurs when water is heated as well as absorbing fluctuations in the incoming water supply pressure. Expansion tanks aka thermal expansion tanks are essentially safety devices to help you minimize the risk of damage to your hot water tank they are an add on to your existing hot water heater and are often installed on the water supply pipe to the water heater normally this is on the wall next to or very close by your hot water tank. What size expansion tank do i need. You can usually get an expansion tank for under 50.

Since water expands when it is heated due to thermal expansion the water heater creates extra water volume every time it heats water. If you have more than one heater on the same or connected system you can either have an expansion tank for each heater or a single larger expansion tank. For example the cold water in a standard 50 gallon water heater expands to 52 gallons when heated to 120 f. If you have a closed system then you ll likely be required to install an expansion tank.

A thermal expansion tank used on a water heater that is not covered by the code should not be required to carry the asme label. Even if you do not have a closed system asking about a water heater expansion tank is still a great idea. Local inspectors or local code requirements may still require the label. That said it may still be a requirement of the owner s insurance carrier or the standard specification of the engineer.

The expansion tank serves as a backup system to prevent overworking your plumbing. This ultimately protects it from damage. That extra water volumeraises the pressurein your water heater to dangerous levels. The excess water volume instead of causing too much pressure on the plumbing rushes into the expansion tank and lowers the pressure in the water heater to safer levels.

One 50 gallon water heater for instance can be served by a 2 gallon expansion tank.