In message , Paul R.
writes

This boiler has driven me to distraction and beyond. In the 5 years I
have owned it I have had nothing but problems. The flow switches fail
about every 12 months, the dhw flow switch housing split and had to be
replaced, the air flow pressure switch has been replaced, the pressure
relief valve has been replaced. the seals failed on the heat exchanger
and had to be replaced, the main cicuit board has also been replaced.
It seems like this bolier was designed to have a life expectancy of 12
months, because that is how long it was trouble free for. Well done
Baxi for selling me a complete and utter lemon. I have probably paid
Baxi more money for spare parts than I originally did for the boiler.
As I write the central heating circuit has failed, the dhw is fine but
the ch makes the water in the boiler boil, so I guess the pump is on
its way out as well now. Ask me if I will ever buy another product
that is remotely linked with the name Baxi. I think I am going to
re-programme it with an axe!

It could be that you have a blockage or that the HE needs a descale

Your final comments seem to be fairly on the mark,

I have had a Vaillant which in 18 years required a secondary heat
exchanger and a fan, but when asked (which I do quite often), I can
honestly say that there are no manufacturers or boilers that I would
recommend any more

I have a Worcester 28i Junior which was installed last year, but then it
was given to me


--
geoff