Woscester Bosch 40cdi what wrong with it? please assist

[sunnyp]

My first post so first let me say hello to all and extend my gratitude to this forum. Now the nitty gritty.

Boiler:WB 40cdi greenstar combi
History: About 2-3 weeks ago i noticed drops of water from underneath the boiler and discovered the flow unit manifold and a fine pin hole leak resulting in a fine spray of water from the DHW out flow bend of the plastic manifold During this time the boiler functioned perfectly. From the research on this forum it gave me the confidence to have a go and change this part. And so i turned off the water, power and drained the bolier. I changed the flow unit careful not to nudge any other part of the boiler and filled the boiler and made sure all rads were full, repressured the boiler and switched back on.

Problem: No more leaking but the boiler fires up and off intermitently when the CH temp reaches about 87 it turns off whhen it drops down to about 60 it fires up. I know with these boilers when the power is interrupted upon starting up they go through a sypon filling program at low output for 10-15mins and a symbol -//- flashes while this happens but after a while the symbol stops but the boiler keeps firing up and off endlessly. The rads close to the boiler heat up. I thought airlock and so i turned off the valves on all the rads and opened one at a time, each one gets hot on individually but when all the rads valves are open just 3 of the 7 rads get hot on 2 luke warm and 2 stone cold and all the rads are full of water. I should mention the DHW works a charm no problems there.
Also no error codes displayed and no flashing lights.

Can any one out there give some insight into what the issues could be and what can be done? If anybody needs me to post more info just ask.

Many thanks

[sunnyp]

got it sorted the plastic pistion that is attached to the diverter valve had unhinged its self and seems like the valve was stuck on Ho****er only mode. Just had to click it back into its place and all is well.