Thermistor for heatbed in Marlin

Good Morning,

I just upgraded my printer with a heatbed. Included in the shipment was a 100k Thermistor with the following spec:

Manufacturer: Murata
Partno: NCP21WF104J03RA
Type: Thermistors - NTC
Resistance: 100 kOhms
Power Rating: 200 mW
Tolerance: 5 %
Termination Style: SMD/SMT
Operating Temperature Range: - 40 C to + 125 C
Current Rating: 0.1 mA

Unfortunately I didn't know which type I should choose in the Marlin firmware. Standard "1" is not working properly.

You shouldn't use any types because that's a non-standard thermistor for RepRap-style printers. With a quick glance It doesn't have a similar β value to any resistors commonly used so no resistance curves will be that similar. You'll need to generate your own thermistor table using this script or if you have a good thermocouple you can use this script by nophead to generate a table based on actual empirical readings.