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September 2, 2026
How Multi-Position Service Valves Work 3D
Most techs learn on standard Schrader valves, where a service hose depressor forces down a spring-loaded core pin. Multi-position service valves are different — there's no spring, no core, and no Schrader seal. Instead, they use a purely mechanical dual-seating design that you control manually with a refrigeration service wrench.
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Flowing nitrogen while brazing does not mean the air was cleared first. Learn how to purge large ACR piping, choose a practical regulator setup, and estimate time and cylinder use.
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First off, the correct acronym for a GFI (ground fault interrupter) is “GFCI” (ground fault circuit interrupter). The purpose is to act as a safety device to protect from electrical shock. GFCIs are important components of electrical safety; they even make an appearance in our electrical safety video. GFCIs can be built into outlets, circuit […]
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It’s always good to reaffirm some of the basics of energy, work, and matter. The five rules below are some of the most basic and important. The First Law of Thermodynamics States that energy cannot be created or destroyed. It can only change forms or be transferred from one object to another. If you’d like […]
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