potterton prima F80 boiler fires up, runs for 2 to 3 minutes then shuts down. Cycle repeats after say 5 minutes. Seems like the hot water cylinder is being heated but not heating the central heating. The over-ride buttons are on for both heating and hot water.

Les Fern, December 2012

just check the heating diverter valve u can open it manually by turning the slider on the side across. if it free and and easy to move is already open if it requires a little pressure then its closed and u are opening manually. if this is the case then its a faulty diverter or time clock it will require checking

kash, December 2012