Hi Andy,
Thanks for your reply.
Yes I have checked the troubleshooting guide (washing machine not heating water) and read the related forum message (Bosch Wfr3267Gb/04 Not Heating). I am sure that water is not heating as I have checked the waste water temp after the wash cycle. In the related forum message PUP79 put a short circuit on the NTC wires back to the PCB and it produced a "temperature too hot" message. I have tried the same, but did not get any message. The machine continued through the wash cycle as normal. I checked resistance on these wires back to the PCB and am getting approx 3.5K. so they appear to be connected OK to the PCB.
While I had the drum out, I cleaned the limescale from the NTC and the element. I have checked resistance of both afterwards, but is it possible that cleaning could have caused a problem. Visually I cannot see any issues and they test OK
I still suspect that I did not connect something correclty etc after re-installing the drum. Is there anything other than the NTC, the element, the pressure switch and the PCB involved in the heating system on a machine>
Many thanks for all assistance