Normally most of the electronic components like capacitors, bridge rectifiers, transistors, IC, diodes, resistors and etc have their own code which is quite easy to read. For example, a 104 capacitor we know that it is a .1 microfarad capacitor, a 1n4007 have the spec of 1000 volt with 1 ampere and so forth. However, for the Thermistor there are so many part numbers and almost all of them have different code which make us as electronic repairer have a hard time trying to locate the part. Usually what i did was to get a replacement from a junk board and i have plenty of junk boards!
I wish that those Thermistor manufacturers could set a standard code so that it would make our life easier especially for those who are new in this repair field. Beginners might have thought of the component could be a Varistor and a wrong replacement might cause the equipment not to function. For your information, if you did not look at the board location you would think that a Varistor is a Thermistor and a Thermistor is a Varistor!