I was watching my HVAC tech add R22 FREON to my air conditioner. While charging the system he tightly squeezed one or two wires with pliers to stop the compressor motor. I saw small sparks. Why was he doing this? He said something about 90 degrees. Is this an accepted practice and will it cause electronics in the air conditioner to fail later? thanks!
Are you sure he wasn't squeezing the wires to run the fan motor, and then releasing them to stop the fan motor.
Yes, he had me turn it on and it was running. It kind of seemed like the couple of minutes he was trying to keep it off with the pliers it would come back on for a second or two 4 or 5 times until he squeezed harder.