No hot water but rads are ok

[rjsimon]

My problem

Syntesi 28e combi - 4 years old
Hot water stopped yesterday no previous problems
Water starts warm then runs cold very quickly
Boiler fires when hot taps switched on but no hot water
Radiators working fine
No warning codes
Pressure fine

Anyone offer a layman's guide to what the problem might be? I doubt I would be able to fix it but would I 'd like to hold a reasonable conversation with whoever does.

Although if straightforward I'm reasonably able - I have tackled dishwasher and washing machine in the past based on good advice form sites like this.

Thanks

Richard

 

[HARALIAN]

get a competent engineer in to assess whats wrong ..... my guess is the div valve needs changing or at least the working parts of it!

 

[Steve69the69Gas]

Yep diverter valve, if it has a microswitch on top - manually activate it and see what happens

 

[rjsimon]

OK, don't see a switch on the valve. So I'll have to get someone in.
Thanks for your help