Central heating problem

[robsm]

Saunier Duval Thermaclassic F24E.
Hot water fine from boiler to all taps , but central heating not working , is fireing up for about 30sec then going out ,then firing up again after about 3-4min and so on , first rad hot , 2nd warm but cold else where , pump working can hear it and feel it pushing the water in the pipes in the hall coming from upstais. Also the pipes on the heating flow and return are hot .On advice have changed PCB and water flow sensor, but still the same .Any ideas All help and advice grateful

 

[Agile]

Here we go!

You have replaced expensive parts based on apparently free "advice" which had not been correct advice rather than paying a professional to properly diagnose the real fault.

It sounds like a flow problem, possibly a stuck diverter valve.

Tony

 

[robsm]

Here we go! Corgi enginer supplied and fitted both ,still same problem, looking local for another.

You have replaced expensive parts based on apparently free "advice" which had not been correct advice rather than paying a professional to properly diagnose the real fault.

It sounds like a flow problem, possibly a stuck diverter valve.

Tony