Hi, could anyone advise on the following problem that I am having with my boiler.

The boiler is set at 80 degrees for heating all seems ok for a hour or two or sometimes when a hot tap is opened, after the boiler reverts back to heating mode the temperature on the display continues to rise above 80 up to 95 hence the boiler cuts out, only the heating illumination is light up and not the ignition lamp. The hot water can still be used at this point as the boiler drops back down to 60 and continues to operate with no problems?

I turn down the room stat and leave the heating off and continue to use the hot water as normal with no problems, after a few hours I can adjust the stat and the heating will come on again as the boiler has probably cooled down.

The boiler has only 2 months of its 5 year warranty period left, I had a Baxi engineer visit twice.

The first visit he changed the heat exchanger and said it was probably due to a dirty system as existing rads were left on the installation (the rads were flushed and additive used with no problems whatsoever over the last 4 years)

The same fault occurred the following day and I phoned Baxi, guess what they said they would not come out until I had the system flushed out. I got a heating engineer to flush the system and fit a Fernox TF1 filter and put the inhibitor back in the system he also changed the actuator as he had a spare one. (he commented that the system was pretty clean and was unlikely to have caused the problem)

I then phoned Baxi and the same engineer reluctantly returned, he replaced the 3 way valve and also the pump and commented that he still thought the problem was due to a blockage!

Guess what the following day the same problem occurred, I phoned Baxi once again and they are refusing to visit untill I flush out the system again.

I am reluctant to pay for this procedure again, does anyone have any idea what could be causing the problem, could it possibly be the circuit board? Any advise would be greatly appreciated.

Regards Paul.

Double post. Answers here
baxi-platinum-combi-28-he-rising-boiler-temperature-t51939.html
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