During showings I’m often asked, ‘What is this “thing” attached to the water heater?’ This ‘thing’ is known as an expansion tank. It helps to reduce the pressure on your water supply lines. If the pressure gets too great it can cause water to seep past the many valves in your plumbing system. There are the obvious valves at the kitchen and bathroom sinks but don’t forget, you have other valves such as those in your washing machine, outside spigots, toilet tanks, utility tubs, water heater pressure relief valves, etc.

Aside from the valves there’s no need to subject the pipe and all the fittings to extra pressure. When water gets hot it naturally expands. This is where the added pressure comes from. The expansion tank has a bladder in it that will expand and make room for the greater volume of the hot water. Think of it as a balloon taking up about half of the space inside the tank. I’m always available to help with real estate questions that come to mind!

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