hot CH but no hot taps?

[jacktrade]

Ive had a britony 80 Combi for a few years now and it always has been good.
A week ago the hot water at the taps didnt warm up.
Now it is a permanent feature.
Now when i turn on hot tap, sounds come from the boiler, but no hot tap water.
Also i checked the pipes going into the boiler ( Hot return CH , and Hot flow CH, and hot flow DW.
Both the CH pipes go hot but the DW pipe stays cold.
How can this happen ??
if the water is being heated, why doesnt the hot DW warm up...I thught it was under same gas unit. Is there some diversion unit that has failed.
I am totally baffled
Help would be appreciated and enlightening.
Thanks

 

[kevplumb]

diverter valve

 

[jacktrade]

thanks kevplumb,, I will try your solution...if it works, I OWE YOU A CIGAR..