Richard Trethewey

Richard Trethewey

Tech Tips written:

Why is 240V called “Single-Phase”?
Why is it called single-phase 240 when there are two opposing phases (or legs)? I wondered why we called two 120v opposing legs “single-phase 240” for years. Then someone pointed out to me that a typical “single-phase” pole transformer only has one power leg entering and two coming out. That freaked me out. How can […]
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Flowing Nitrogen? Make Sure You Purged First
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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What is a GFI?
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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Podcast guest:

Richard w/ This Old House Shares His Story
Richard Trethewey from This Old House joins Bryan on the podcast and tells his incredible story and shares some encouragement and laughs. Richard works with his sons, Ross and Evan. He has always worked in a family business and then left it to start his own with his sons. Family businesses truly are the backbone […]
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