Hi, go to the baxi web site and look for their Interpart link or paste this into your browser.
http://www.interpartspares.co.uk/documents/index.php
Make sure you have java enabled in your browser then select search technical documentation library. Then follow the instructions (suggest you select not to install Grafixview) then select Baxi, backboiler, bermuda and the 552 model. You can get installation manual, exploded view, parts lists etc.
Steve Willis, September 2007