I need someones advice!!!

Im working on a project which needs a temperature control circuit to activate a relay. The project is due in next week so i desperately desperately need someones help!!!! please please please!!

http://www.electronic-kits-and-projects.co...s/1000/1048.pdf is a link to the info sheet of the circuit i have purchased. However the temperature range of this circuit is 20-80 degrees and i need it within 2-8.
I heard that i only need to change the variable resistor (is that also called a potentiometer?) to a 4.7k. Would that work?
Basically i need the relay to switch when the temperature gets to about 8 degrees and then switch back when it gets around 4.

Please also understand that I do not wish to over complecate it as I know nothing about electronics (wish i listened in class now) so im after the simplest solution!!

Would really appreciate any help!!
Many thanks
Brendan

 

Forgot to mention the thermistor is negative coefficient

At room temperature it is 1k
at 0 degrees it is 2.7k

 

Originally posted by brendyboy@Apr 19 2006, 10:42 AM
However the temperature range of this circuit is 20-80 degrees and i need it within 2-8.
I heard that i only need to change the variable resistor (is that also called a potentiometer?) to a 4.7k. Would that work?

[post=16320]Quoted post[/post]​

The requirement looks like a refrigerator thermostat.

You have provided no component values. It is difficult to answer.

Call the company and talk to their engineer.