On an energized, intact circuit, you will read voltage across an OPEN switch when testing with a voltmeter. However, you probably won't read significant voltage across a CLOSED switch. Both sides of a closed switch are electrically identical (or at least very close). Therefore, there should be no movement of electrons between the leads of […]

This article is part 5 of a 5-part series on troubleshooting by Senior Refrigeration and HVAC tech Jeremy Smith. This step might be the most challenging part of troubleshooting. We've got a “Most Likely candidate” for the trouble, but we don't know for certain that's what is wrong. So, we have to combine our customer […]

Belly band crankcase heater When I first started in the trade as an apprentice, we worked on many Trane heat pumps that used crankcase heaters. These crankcase heaters slid into the compressor sump on the big orange Tyler reciprocating compressors. They looked like the one in the picture below. It was very common for these […]