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.
This part is present 49 different boilers in the Alpha range including the Alpha CD12S, CD12S LPG, CD18S, CD18S LPG.
At the bottom of the page is an appliance table with the links to all boilers that contain this part.
We recommend that all parts are fitted by a fully qualified gas safe certified technical. If you require any help locating a part, please feel free to contact us.