Combination boiler only firing up from one tap

[gkular]

I have a combination boiler that is two years old. It is a worcester bosch. System was installed and worked perfectly for two years.

A few days ago the hot water from all the taps in the house became intermittent. I ran one of the taps and I could see that
the boiler was trying to ignite but was failing to do so.

However one of the taps works perfectly and the boiler fires up no problems. This tap is the closest to the boiler, I don’t know if that makes a difference.

All the taps in the house are mixer taps. I ran them all this morning for about half an hour and the problem seemed to have resolved itself. Then when I put them on exteme hot the boiler stopped working, again trying to fire but failing. However as stated already the one nearest to the bathroom worked without any issues.

All the taps in the house are less than two years old.

Had engineer out and he checked an internal metal filter and that wasn’t clogged. Heating seems to work fine.
He thinks the heat plate needs replacing.

System was powerflused two years ago, I cant see how the heat plate could go so quickly. Also the hot water pressure is a bit low from all the taps - apart from the one that works fine!

Any ideas?

 

[mysteryman]

Check if it is still in warranty, it may be. Sounds like the flow sensor in the boiler, rather than a blockage.