My heating system is 6 years old and comprises a Potterton Suprima 50 Boiler, EP2002 Programmer and a Tribune Premier TP210B Hot water cylinder. The problem is that everything works ok until the water is hot then the heating shuts off. If you then run off hot water the heating will fire up again. The PCB was changed in the boiler but made no difference. Any suggestions gratefully received or recommendation for a reliable heating engineer in the Runcorn Area.[/u]