Hot Water intermittently Cutting In & Out

[ajf01923]

My Alpha Ocean 280p combi boiler intermittently cuts in and out when delivering hot water only. Alpha themselves suggested replacing the DHW temperature sensor - which has been done - yets the issue is still there.
Any help would be great.

 

[Mike Jackson]

Possibly the diaphragm in the diverter on the way out.

Mike

 

[ajf01923]

I should have added the diverter valve was replaced 6 weeks ago. I've managed to nail the issue down to when the (hot) taps are fully open. When open half way the problem does not occur. Any ideas what this could be?

 

[leakylea]

i would think that your maximum gas pressure on the dhw is too high
check with MI and set accordingly sometimes a restricted secondary heat exchanger will cause this