Fan cooling too much and too frequently

I have had few issues with my K8200 until now. The jobs are running fine for around 15 minutes and then the extrusion stops due to the extruder being too cool. I have covered the fan which seems to do the trick in terms of preventing the temperature drop - however the layers are now not cooling sufficiently and remain very soft when subsequent layers are applied. Clearly I can’t just cover the fan all the time. This has never been an issue before and the location of the fan and its angle have not been altered in any way. Any suggestions?

Just a guess

Maybe a weak solder connection going to the heating element or the thermistor.
The heating element may be going bad.

I’m by no means an expert - but if it was the heating element wouldn’t it continue to be a problem even if I covered the fan? Also I would have thought that the thermistor would simply detect the temperature and stop extrusion if the temperature drops to a certain level; so therefore I thought it was more of a fan/settings problem. Should the fan be running constantly when the printing job is running?

You should post this in the K8200 section.

Since this has not been an issue before and nothing has been changed then I would look at the soldering.
These machine vibrate a lot.
If there is a weak solder joint then the vibration maybe causing an open to the heating element.
How much does the heat drop?
How cold is the room you are printing in?
Is the LED for the extruder heater on all of the time?

Good point - I didn’t even realise I was in the wrong section so that shows my level!! As for the heat dropping it goes down to around 130-140. The room is normal room temperature. Not sure about the LED - I will have a look at this on my next try.