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Richard Trethewey
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Tech Tips written:

What is the Difference Between ACH & ACH50?
This photo is of a blower door test we performed at my own house using a Retrotec blower door. You will notice the 15-passenger van outside the window, which is a dead giveaway. A blower door is used to measure the tightness of a building and is often discussed in terms of an ACH50 number. […]
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Which Valve Do I Open First?
Testo 557 vacuum gauge and Appion core removal tools shown I've had a change of heart. Back in the early 2000s, during the big construction boom, I did many system startups on residential units for a large company I worked for. When installers ran the line sets prior to startup, they weren't always very careful […]
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The 1/7 (or 1/10) Rule for Oxy-Acetylene Torch Tips
We already know that oxy-acetylene torches have a lot of safety considerations attached: don’t oil regulator threads, bubble-test your hoses, you get the picture. But there’s one more we haven’t really covered: the 1/7 rule (or 1/10 rule, based on the latest industry guidance).  This commonly cited rule reduces the likelihood of flammable acetone coming […]
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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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