<P> An expansion tank or expansion vessel is a small tank used to protect closed ( not open to atmospheric pressure ) water heating systems and domestic hot water systems from excessive pressure . The tank is partially filled with air , whose compressibility cushions shock caused by water hammer and absorbs excess water pressure caused by thermal expansion . </P>
<P> An expansion tank or expansion vessel is a small tank used to protect closed ( not open to atmospheric pressure ) water heating systems and domestic hot water systems from excessive pressure . The tank is partially filled with air , whose compressibility cushions shock caused by water hammer and absorbs excess water pressure caused by thermal expansion . </P>
purpose of expansion tank on a hot water heater
purpose of expansion tank on a hot water heater
protect closed ( not open to atmospheric pressure ) water heating systems and domestic hot water systems from excessive pressure
protect closed ( not open to atmospheric pressure ) water heating systems and domestic hot water systems from excessive pressure