Most will already know this for those that don't its a good article.
http://www.ho****er.com/lit/bulletin/tb-a023-06.pdf
http://www.ho****er.com/lit/bulletin/tb-a023-06.pdf
Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
Reply to the thread, titled "Air pressure switch testing" which is posted in Air Sourced Heat Pumps Advice Forum on Plumbers Forums.
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