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John Refrigeration Basics Quiz June 13, 2021, 4:29 pm
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Don’t Fall for Unsafe Practices: Heights in HVAC
DISCLAIMER: HVAC School is NOT an official OSHA safety training resource! Although we provide safety tips in good faith, our website is not a substitute for safety training from an authorized OSHA training source. Many things may deter people from working in the HVAC industry. Perhaps surprisingly, exposure to heights could be the deal-breaker. (Not […]Read more
Oxyacetylene Torches: Tips and Operation
Everyone in the HVAC/R trade uses some type of torch to braze or solder alloys together. So, what is the proper way to handle an oxyacetylene torch? It turns out that there’s more than one right answer. Depending on which torch rig you use, the manufacturer’s manuals for operation may vary. Everyone (hopefully) knows […]Read more
What does "RES" mean on a contactor or relay?
Go to your truck, pick up a contactor, and look at it closely. You may find some interesting ratings you never noticed—things like terminal ambient temperature ratings and torque specs. One reading you may overlook is the RES AMPACITY of the contactor or relay. The RES rating is the RESISTIVE LOAD AMPACITY (amperage capacity) or rating. […]Read more