Saunier Durval 620 Heating but no hotwater help please

[cuffer]

Hello

I've read lots but never posted before

I'm Gas Safe registered and live in the North west

I have a flat in London with a Saunier Durval 620

The Heatings working but no hot water

I can't get down for about two weeks ( mother passed away)
and My tennants need hot water
Any Ideas
Not sure how these work but tennat says the following

Boiler fires up when hot tap is turned on but water cool
flow pipe is heating up which may suggest diverter valve or
heat exchanger blockage but not sure how the hot water works on this boiler.
I don't have a boiler manual so would appreciate any help

regards

 

[kevplumb]

I don't have a boiler manual so would appreciate any help

do you think an e mail adress would help