Hello, and thank you for using this service. I'll be helping you with your problem today.
So most technicians will have a multimeter they can just plug a thermocouple into and the thermocouple is specific to the multimeter, but I'm not sure what you have exactly. If your unit doesn't have a thermocouple to test, the best option is going to be getting a digital oven thermometer
and sticking the metal probe into the vent where the lint filter goes to measure the temperature and then shutting the door.
You can get this one at targe for about $15. CLICK HERE
It's really good to have for checking a dryer out for all reasons. It will let you know if you have a clogged vent, or if the temperature isn't cycling properly, or whatnot. The temperature should cycle from about 115 degrees up to 205 degrees or so normally on high heat. The first cycle will be off, but don't worry about the first cycle too much. If the unit goes all the way up to something like 240 degrees quickly and slowly declines back to 120 or so, that lets you know you have a clogged vent. It'll take a while to get used to, but as time goes on, you'll understand what a normal rising temperature rate is and what slow is and such.
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