When you work on a heat pump system and want to test defrost, you can follow many different test procedures to test the board and sensors. Most involve “forcing” a defrost by shorting out pins on the board or advancing the time of the defrost initiation and installing a factory-provided pin jumper. Lots of pins […]

Take a look at the specs from this Copeland scroll compressor pulled from the Copeland Mobile App (which is an incredible app, by the way). These specs are for a single-phase compressor, so the amperages listed are based on an amperage reading from the wire connected to the common terminal. LRA is the locked rotor […]

This topic came up because I was testing out the new MR45 digital recovery machine. That machine goes off by itself when it hits a 20″ Hg vacuum. It's a cool feature, but it is good to know when that level of vacuum is overkill and when it's not enough according to EPA requirements. You […]