Nozzle heater issue try this to solve. W50
1. First update to last firmware / ALSO DO A CHECK CABLE FIRST!!!
2. Clean your nozzle
3. Take a look between heater block and heat sink can get loose then plastic can stick between then cause temperature issue even fail your print.
remove the nozzle heat sink clean it then tight it back.
4. Go to preferences / material / choose your material / print settings then change Standby Temperature closer to your actual printing temp. *If you still have temp issue.
5.Still have a problem make a request to your reseller or BCN3D Cause they have a bad batch of heater elements. LOL
Thank you for posting this guide regarding the temperature issues on the hotend.
It is true that we had a batch of hotend cables that was defective so if you see any irregular and/or unstable temperature please contact with us via the contact form.