baxi duotec e50 boiler error

[chalkie7]

Hi, I'm hoping someone here may be able to help me out with an issue I have with my baxi duotec boiler. Basically, the hot water temperature has been fluctuating quite alot, dropping in temp then raising again whilst showering. I have had an engineer out who has changed the thermistor, but I am still having the same issue. I have tried a few bits tonight to try and see what is actually happening at the boiler when a dip in temp occurs, and it looks like the boiler calls for heat, races right up to 90 degrees, the call for heat is cancelled, the temp drops rapidly down to around 70 degrees and I briefly see error code E50. Heat is then called for once again, and the cycle repeats. E50 seems to point to the thermistor which has only just been replaced last week! Any advice would be greatly received!

 

[ShaunCorbs]

Heatings fine I guess ?

 

[chalkie7]

Yes, heating side is spot on

 

[ShaunCorbs]

Would say plate then

 

[chalkie7]

Would say plate then

The boiler is coming up to 15 years old, so maybe it's time for a new boiler.

 

[cjg]

new p.h. ex. that will be alot cheaper than a new boiler.