Are expansion tanks really 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 system.

Why is an expansion tank required?

Its purpose is to deal with thermal expansion of water as it heats up in the water heater – to prevent water pressure from getting too high. If water pressure gets high enough it can damage valves in plumbing fixtures, joints in supply pipes and even the water heater.

What happens if expansion tank pressure is too low?

If the precharge pressure is too low the tank may be excessivly full of water even before the thermal expansion takes place which may limit room for expansion, add additional weight to the tank, and, or, stress the tank bladder. These factors may reduce its service life.

Do you need an expansion tank for your home?

You see, homes have either an open or a closed plumbing system. A closed plumbing system prevents water from flowing in the reverse direction (i.e., water won’t flow back into city lines once it enters your home’s pipes). Since most new homes are built with a closed plumbing system, chances are, you’ll need an expansion tank.

What should the pressure be in an expansion tank?

The importance of pressurizing the air is that it determines the pressure that the chilled water must achieve before the expansion tank accepts volume. For example, the closed tank has a pressure of 14.7 psia. As the chilled water pressure increases above 14.7 psia, the chilled water will flow into the expansion tank.

How does an expansion tank ( CHW ) work?

It is simply a closed tank with a connection to the chilled water system. The closed tank has extra space that is filled with air, when the temperature in the system is cold. As the temperature within the chilled water system rises, the volume expands and fills the empty space within the tank. Expansion Tank (CHW)-4

What does an expansion tank on a water heater look like?

An expansion tank looks like a mini tank or boiler, and typically sits on top of, or adjacent to, the water heater. They come in many different sizes, depending on your water pressure, the size of the actual water heater, and the temperature the water is heated to. As water is heated,…

You see, homes have either an open or a closed plumbing system. A closed plumbing system prevents water from flowing in the reverse direction (i.e., water won’t flow back into city lines once it enters your home’s pipes). Since most new homes are built with a closed plumbing system, chances are, you’ll need an expansion tank.

Where is the expansion tank on a water heater?

An expansion tank looks like a propane tank, and it’s located above the water heater. Like water heaters, expansion tanks are expected to be strapped in as a way to protect the tanks from spilling over in the event of an earthquake. If you see a second tank (usually white, beige, or blue) over your water tank, that’s the expansion tank.

What happens to a water tank when it expands?

When the water volume expands, it puts extra pressure on the tank. Over time, after continuous expanding and contracting, the tank will weaken (think of bending a paper clip back and forth—eventually it will break). And that’s where an expansion tank comes in.

Can a large expansion tank cause relief valve discharge?

The standard is to select an expansion tank that is larger than necessary rather than select one that is too small. This is because a tank that is too small can cause relief valve discharge. On the other hand, if the tank is too big, it has no negative impacts on your plumbing.