I had an old-timer tell me that you can never connect two transformers together because they will “fight one another.” If you are anything like me (and heaven help you if you are), a cartoon in your head starts playing whenever someone says something like that. In this case, I imagine two transformers with boxing […]

Recommended Duct Velocities (FPM) Duct Type Residential Commercial / Institutional Industrial Main Ducts 700 – 900 1000 – 1300 1200 – 1800 Branch Ducts 500 – 700 600 – 900 800 – 1000   As service technicians, we are often expected to understand a bit about design to diagnose a problem fully. Duct velocity has many […]

Oil pressure controls, oil failure controls, oil safety controls… They’re a pain in the neck when they trip, and diagnosing those problems can really tax even the best of techs. As semi-hermetic compressors get larger, they can no longer rely on simple splash or “sling” type lubrication strategies where oil is just flung around inside […]