TLV, Armstrong, Spirac Sarco and Yarway all have very good booklets on steam trap operation, selection and troubleshooting. I'd check with your vendor and ask him for some information.
What is the problem you are seeing with this trap, what sort of equipment is it on or is this more of a general question? Bimetallics can be designed to either discharge the condensate at either close to saturation temperatures or subcooled a certain amount if I remember correctly and that makes a big difference in what you would see with a trap that is operating correctly versus one that has failed.