To ask an engineering question please visit our forum site at Eng-Tips.

Hello all, I am new to the site. I am an HVAC Professional, I own my business and I trying to find a way to use a thermistor as a simple relay for a 24 volt ac circuit. The goal is to have a thermistor that would allow the 24 volt ac voltage pass through when a specific temperature is reached. For example, the voltage circuit would be open until the temp reached 35 degrees, the thermistor would then close the circuit and would stay closed at any temp higher than 35, I have seen this done in an example video on you tube showing a light being turned on when the thermistor is heated with a blow dryer. Please let me know if you can help with the exact type of thermistor and specs related to it. thank you