Expansion tanks are critical components to your Plumbing and Hydronic Heating systems because they prevent your pumps, pipes and other components from bursting.

Expansion tanks are needed by hydronic heating systems and most plumbing systems to contain the water as it expands when it starts to heat up.

When the system is first filled with cold water from your supply line, the pre-charge pressure of the expansion tank is equal to the supply line fill pressure, this pressure keeps the diaphragm flush against the tank. However, as the temperature of the water in the system increases it expands and the expansion tank diaphragm flexes against the air cushion to absorb the added pressure, the Pre-Charge tank pressure is usually 12 DPI for Hydronic Heating and 44DPI for a plumbing system. Call us at 919-293-1221 to find out more about expansion tanks.