DIY Temperature Controlled Window Fan

[m2rechtin]

Hello,

I built a fan that will only blow air into a room when the temperature outside is lower than the temperature inside. Check it out and let me know what you think!

-Michael

[Altair]

Thanks m2rechtin! We've added your Temperature-Controlled Fan to our Heating and Cooling category,
as well as to your builder page: m2rechtin's Homemade Tools. Your receipt:

Temperature-Controlled Fan by m2rechtin

tags: fan

[JKeetonKnives]

Dude that's pretty awesome! Cool idea!

[jdurand]

If you ever need to do something like that tiny and cheap, you can use two silicon diodes (1N4148) as sensors along with an 8-pin comparator chip and two resistors. You probably need a transistor to help the comparator drive a DC fan directly or a relay for an AC fan. Won't give any readout but will switch fan on/off based on which sensor is hotter.

[m2rechtin]

Thanks for the tips jdurand! I will have to try that out.

[jdurand]

Thanks for the tips jdurand! I will have to try that out.

Let me know if you need any circuit help with that, you can also add hystorisis so there's some room between the turn on and turn off points.