Are expansion tanks needed on hot water heaters?

So, are water heater expansion tanks required? Most cities require residential plumbing systems to be closed water heater systems. When a new water heater is installed on a closed system, an expansion tank is required by building codes. Expansion tanks are not required for open plumbing systems.

What is the purpose of a water heater expansion tank?

The expansion tank is designed to handle the thermal expansion of water as it heats up in the water heater, preventing excessive water pressure. If water pressure gets to high it can damage valves in plumbing fixtures, joints in supply pipes and the water heater itself.

Is an expansion tank necessary?

An expansion tank is always highly recommended if you have a 'closed-loop system' caused by any kind of check valve or pressure regulating valve installed on your house's water supply line. ... However, the long-term wear and tear of this excess pressure can reduce the life expectancy of everything in your plumbing

Will a bad expansion tank cause low water pressure?

Before installing an expansion tank, measure the tank's air pressure charge. When taken from the box, the air pressure in the expansion tanks will likely be lower than your home's water pressure.

What happens when an expansion tank fails?

Often the diaphragm dividing the two systems will fail, causing the two systems to become one. When this happens, the expansion tank turns into a “dead leg” that will eventually cause damage and premature failure to your water heate