We replaced this customers boiler which was over 20 years old with a new Worcester-Bosch Life boiler with 10 years guarantee, due to the age of the pipework and radiators the customer was concerned about leaks and for this reason we could not seal the system or add any pressure to it , so we decided to fit a regular type boiler and replaced all their controls and altered some of the pipework to suit the new boiler whilst not adding any pressure to the system .Took a while to fill due to the amount of radiators in the system but the boiler is working great and the customer is delighted.