Thermistor temp controller

Thread Starter


Joined Oct 28, 2011
How do I build or preferrably where can I buy the parts or better yet, an assembly for a temperature controller, for inclusion in my product, that has an adjustable range of 160-220F and has a normally closed output that will control a "Standard Automotive Relay". The operating voltage will be 12VDC, the desired delta T would be + - 5 degrees. Low quantity, ~12 per month.


Joined Mar 24, 2008
I found this in the Completed Projects Forum, which is (as the title states) for completed projects. I moved it here so it could get attention.

What is the product for?


Joined Jul 17, 2007
I would be willing to bet money that the intent of the project is to control an automotive radiator fan motor.

If that is indeed the case, then all of the components used would have to be specified for use in the automotive temperature range (-40°C to +125°C), and the discussion of which circuit would be beyond the scope of these Forums.

If it IS for an automotive application, then I suggest you check out some of the automotive-project-friendly sites listed in this topic:

Simply omitting the fact that it's automotive and re-posting would do yourself and your prospective customers a great disservice, as your product would not be reliable.