Diode how to choose it?

Vertex 3D Printer Vertex - Issues while printing
1

It’s 190°C but the fillament won’t get out so what’s the problem ?? it might be in the diode or in what ??
because when printer is off it shows that it’s 183°C but when i touch it it appears so cold !!!

2

Indeed sounds like a faulty sensor.
You can request a spare part from
http://support.velleman.eu