Fan controlled off values of 2 thermistors

Hopefully someone has done this before. I am hoping to control a fan off of the values given by 2 thermistors. Heres the situation. I am setting up a fresh air fan in my house that forces fresh air from the outside, to the inside of the home. But the fan would only enable given the temp of the thermistor on the outside of the house, is less than the temp of the thermistor on the inside of the home. Anyone know of any project that would have a similar coding to this?

There are many, many tutorials that show you how to read a single thermistor.

Start with one of those, and once you get everything working properly and understand the code and operating principles, it will be very simple to add another thermistor.

Two factory calibrated digital DS18B20 sensors could be easier.

Search for "waterproof DS18B20" on ebay.
leo..

Wawa:
Search for "waterproof DS18B20" on eBay.

And don't believe it. :roll_eyes:

Nevertheless, since it is only for air temperature with the possibility of occasional moisture, they will probably do. :grinning:

Unfortunately that's what they are called.
Gives at least some protection for outside use.
Leo..

As a matter of interest, and nothing to do with the coding, I was once told by an hvac guy that sucking is better than forcing.

So you would put a duct to the centre, and have the fan extract thru that duct. The incoming air from the windows and vents then rushes in from the outside to fill that void.