Before You Ask...About Pressures

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Before You Ask...About Pressures

Postby CEO1 » Sat May 17, 2014 6:36 pm

So many beginners come on forums and ask something like, "My suction pressure is low, but the head pressure is about normal (or high)", or "The head pressure is high and the suction pressure is high", or some other combination of pressures and/or superheat and/or subcooling.

The majority of refrigerant system issues are the same ones occurring over and over and over. And a lot of beginner techs haven't fully come to understand the pressures and why they do what they do.

The chart below is what I call "Recipe Diagnostics"...just look for your symptoms (they'll be in one of the horizontal lines), then find the cause of the symptoms under the "Problem" heading on the left...the link is to another post that expands on the chart...

(Note: "High" and "Low" don't necessarily mean excessively high or low...just highER or lowER than "Normal" for a given system operating under a given set of conditions)

Common Problems
One of the MFIC's...

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