Ecofit pure 830 hot water problem

[Andrew Edmondson]

I wondered about this too. I don't know where it is. I can only see the flow/return sensors on the parts list.
On the previous boiler, a Halstead Finest Gold, the DHW thermistor needed replacing every couple of years.

 

[Johntheo5]

The wiring schematics doesn't reference it either, it just shows flow&return temperature sensors, the DHW temperature is possibly derived but would seem strange when/if the DHW temperature is settable?. Vaillant should inform if one is installed and where?.
Some other models do show one.

 

[Andrew Edmondson]

Yes, I agree it is strange. I assumed that the rates of flow and difference in heating flow/return temperatures allowed the software to calculate the HW temperature.

 

[Andrew Edmondson]

Well it was a faulty replacement flow sensor after all. The packaging was slightly damaged, so perhaps it was damaged in transit.
However, I replaced the diverter valve and PCB earlier in an attempt to fix the problem. Now I have great HW but the boiler will not fire up high for heating. I'll make a separate post on this, as I have tried everything I have come across in the manual and forums.
Thanks for the help. I've learned a bit more about this boiler.