Thermometer Placement re: methanol etc...

[crackpotjenkins]

So I just bought a still. It is a stainless steel 3g potstill with a 24" reflux tower. The thermometer is placed through a #10 bung that plugs the top of the tower. So the thermometer hangs down into the top of the tower about 3 inches.
Before this still I was using a 4 g potstill also with a 24" tower that I had made myself. In this earlier still the thermometer was inserted into the lid of the pot not into the tower. The thermometer didn't touch the wash inside only the vapors.
The range I have found for safe ethanol collection is between 170 and 180 degrees F and even better only 172-176...right?
With my first still (the one I made) I had no problem. This temp. range worked well, everything went smoothly.
With this new still of mine with the thermometer in the top of the reflux tower I don't even begin to get any distillate until the thermometer reads near 185 and the tails don't appear to be coming until the 202 marker.
Any ideas why this might be happening?
It is a digital thermometer...I hadn't thought about it until now but I've never calibrated it. That might be it.
I'll test that theory and in the mean time please help...
Thanks

[Prairiepiss]

Edited. Removed incorrect information.

You may want to look in to replacing that rubber plug with a non synthetic plug that is safe to be in the alcohol vapor path.

Edited.
After reading my post and your post I figured out I posted misinformation pertaining to your Reflux column. Sory.

[Dnderhead]

the thermometer will read the vapor temperature for the percent of alcohol,as its not 100% alcohol
it wont read 78.3c/172f. so if the vapor is lower in alcohol the the temperature will be higher.
this will change throughout the run as the alcohol is depleted.

[blanikdog]

Superb post PP. My smashing days are over. <sigh>

Maybe a quick glance at the new distillers "Reading Lounge" would also be of benefit.

[Prairiepiss]

Superb post PP. My smashing days are over. <sigh>

Well Blanikdog I removed it. After reading he replaced his pot still with a reflux still. I thought the thread I pointed him to would be incorrect. As it is about thermometers in pot stills. Here is that thread. But it probably still should be read.
http://homedistiller.org/forum/viewtopi ... 46&t=13294