Tel Tru Stem Question

After several usages with my TelTru thermometer, the stem has acquired a thin, shiney and brown coating resembling solidified combustion/grease products. The stem appears as though it's been varnished.

Should the stem be periodically cleaned all the way down to the metal to ensure accuracy?

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by tjkoko:
After several usages with my TelTru thermometer, the stem has acquired a thin, shiney and brown coating resembling solidified combustion/grease products. The stem appears as though it's been varnished.

Should the stem be periodically cleaned all the way down to the metal to ensure accuracy? </div></BLOCKQUOTE>

Anything on the stem will have some insulating effect, slowing the response of the thermometer to changes in temperature. In practical terms, it may be too small an effect to make any difference. Cleaning it down to bare metal is probably not a bad idea, though. Just be gentle.

I use the 4" inch stem 3" dial Tel-Tru's on both of my WSM's, read your post and curiosity killed the cat. Did the boiling water check and both were reading around 212*, which is perfectly correct for my residence. Both had the shiney carbon coating, in which TJKOKO spoke of. When I pulled the stem from the boiling water I noticed the tip of the stem was shining like new. Then took a plastic scouring pad and dipped the thermometer back in the hot water for a few seconds and lightly gave it a few turns while I grasp it with the pad. Now they are both shiney and free of the carbon build up. In my opinion, I don't think the build up hurt the accuracy of the Tel-Tru's since it was so thin, but at least I found a safe way to clean the stems when it gets a little heavier than my liking.