My setup is a relay on the 240V line, a programmed temp swing of 5deg, and cool down period of 5 minutes after ac shutdown before it can turn on again to avoid damaging the compressor.

In this quick Arduino tutorial I will explain how you can control a relay using the Arduino Board, one 1K and one 10K resistors, 1 BC547 transistor, one 6V or 12V relay, one 1N4007 diode and a 12V fan ...

Most of North America has been locked in a record-setting heat wave for the last two weeks, and cheap window AC units are flying out of the local big-box stores. Not all of these discount units und… ...