Hi I am thinking to replace my ageing Alpha CD24R with a Bosch equivalent, I have a few quotes which seemed fair, until today we had a company turned up, he really had a good look round. Far longer than the others, (one i had to send pictures ? And he quoted me the pics that I supplied?) He informed me that the copper pipes going to the cylinder are 22mm and the Bosch requires a 28mm . Connecting directly to my old pipes , I may/will get a problem with the heat exchanger at a later date. he recommended using another company boiler . he also told me that with the 22mm pipes the system will not as efficient . We have been in this for 3 years and I have noted that the radiators get warm not hot. Is he honest , or is he toting for more work?? Could any one clarify