As part of a revamp program for my home solar system, I wanted a controller to manage a small vent fan in the electrical enclosure for the power system.

Here is how I did it.

Step 1: The Controller.

This neat little controller is temperature based and offers real time indication of temperature on the middle led display.

For cooling purposes the left display must be set high at the cutoff temperature and the right display must be set low at the start temperature.

Adjustment is super easy with the pushbutton switches for each display.

I think this is the very best temperature controller on the market for hobby projects.

The one I ordered from Amazon.com can be used from 20v up to 30vdc.

Step 2: The New Fan.

The original fan is a 12v unit but I got a 24v rated 80mm fan for simplicity in wiring.

Step 3: Installing Into the Cabinet.

See how dusty the original fan is after a year of no cleaning? Time to remove this old unit and replace with the new one.

The 24v supply I got right on the lid from my wind turbine setup.

The thermal sensor was placed high enough onto the lid to sample the internal temperature. I was careful not to place it near the fan to prevent fast cooling of the sensor.

Step 4: Testing!

With a start temperature of 35c, I used my fingers to warm the sensor to make the fan turn on. Once on I removed my fingers and when the temperature dropped to 32c it came off. Perfect operation!

Step 5: Completion!

Now my new fan should last very long since it will only be on when needed. The original was on continously. Also this new approach will reduce the build up of dust and lint within the enclosure.

I'm happy with the installation and this is yet another important item off the checklist!

I hope fellow hobbyists have found this instructable interesting.