I just got an Arduino micro controller and I'm getting ready to integrate it into my HERMSish setup. I've been using a PID with a K-type thermocouple that works well with the PID controller.
I've been reading around about the Ardunio and temperature control and it sounds like thermocouples are not the best option. A thermocouple is noisy and requires a $12 chip like this MAX6675. http://www.sparkfun.com/products/307
It is also difficult to read multiple sensors with one Arduino.
A thermoresistor may be a better option or a Digital Temperature Sensor like the DS18B20 http://www.sparkfun.com/products/245
I need a stainless 1/4" probe that I can use with a compression fitting in my setup. It should interface well with an Arduino and still have the ability to read up to 4 probes and run a 7 segment display http://www.sparkfun.com/products/9480
. Low cost (No $12.00 MAX6675 needed) and glass wire-wrap/insulation is a plus.
Thanks for your input!