Hot Water on Potterton Performa 28 Combi

[rajshah]

Hi,
Can someone help me, I have 5 year old Potterton Proforma 28 combi boiler and I am having problem with hot water supply. Every few hours after you turn hot water, red light on the boiler flashes so I reset it and hot water starts again then after few hours later same thing happens again and I have to reset it to get hot water.
Few months back I changed the 3way Valve Assy.

Your help would be appericiated.

 

[jackecole]

sounds like secondary (hw) heat exchanger is blocked up (sludge/scale etc)

 

[peterbaxi]

need more info the three lights what are they doing solid off flashing?

 

[rajshah]

sounds like secondary (hw) heat exchanger is blocked up (sludge/scale etc)

Do you know how can I clear it.

Thanks for your response.

 

[rajshah]

need more info the three lights what are they doing solid off flashing?

Only one red light flashes.