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Why Buy – Thermal Expansion Tanks

Why Buy – Thermal Expansion Tanks

9th Oct 2020

Most of us learned at some point that water expands as it gets heated and that holds true for the water in your water heater as well. This expansion within your tank can lead to an increase in pressure. Too much of that pressure can eventually lead to damage in your pipes and valves.

With older residential and commercial water heaters, the excess pressure in the tank would just flow back into the municipal water line. Newer regulations no longer allow for this overflow relief. Instead, the pressure is either constrained in the system, or is relieved by the use of a thermal expansion tank.

To mitigate the potential risk involved with high pressures in your commercial water heater or residential water heater, a thermal expansion tank is installed. This expansion tank helps by allowing the excess water caused by this increase in pressure to flow into the tank, thus relieving the pressure in the lines or pipes.

Here at Commercial Water Heater Sales, we have two options to choose from: a 2 gallon tank and a 4.5 gallon tank. Which size is right for you will depend on the system you are upgrading or installing. Both the size of the residential or commercial water heater and the pressure from your municipal water line will determine your needs. For help with picking the right size tank, please call us at 714-558-8838, and one of our commercial water heater specialists can assist you.

With a small amount of plumbing experience or a little bit of DIY knowhow, you can install your thermal expansion tank yourself. Simply check the pressure in the tank with a common tire pressure gauge. Then, using a hand air pump, slowly fill the tank to the pressure matching that of the psi in your water line. Always install the tank on the cold water line; there are numerous videos online that can help you through this process. Turn on a sink and let the water flow until a steady stream is achieved. You’re done!

Thermal expansion tanks are an inexpensive yet critical safety device to help expand the life of your residential or commercial water heater and plumbing system. We would love to help you choose the right expansion tank and water heater for your application. Please call us to learn more!