We had a worcester bosch greenstar 12ri (not combi) installed in February and have had no end of problems ranging from leaking to joints to the condensing pipe exiting at an upwards angle so condensate was flowing back into the boiler! The latest (radiators only coming on when heating was on) was diagnosed as a faulty diverter valvle. We have just had the new one fitted and now all the upstairs radiators work but none of the downstairs. The pipes coming down the wall from upstairs are stone cold. I'm afraid I have lost all faith in the installer who seems to take 3 or 4 visits to diagnose. Somebody else suggested the flow and return may have been mixed up. Before I call him back again - has anyone any idea what the problem might be this time? Its a small terrace house with three radiators upstairs and only two downstairs.
Cheers
Cheers