What vacuum measurement indicates a good vacuum level in a refrigeration system?

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Multiple Choice

What vacuum measurement indicates a good vacuum level in a refrigeration system?

Vacuum level in refrigeration work is read in inches of mercury on a vacuum gauge. On this scale, higher numbers mean more vacuum, with about 30 inHg representing near-full vacuum. A good vacuum during evacuation is around 29.9 inHg, showing you’ve removed most air and moisture from the system. Reading 30 inHg is at or beyond the instrument’s limit and isn’t typically seen; 28.5 inHg and 29 inHg indicate less vacuum than 29.9, meaning the system hasn’t reached as deep a vacuum. So, 29.9 inHg is the best indication of a good vacuum.

Vacuum level in refrigeration work is read in inches of mercury on a vacuum gauge. On this scale, higher numbers mean more vacuum, with about 30 inHg representing near-full vacuum. A good vacuum during evacuation is around 29.9 inHg, showing you’ve removed most air and moisture from the system. Reading 30 inHg is at or beyond the instrument’s limit and isn’t typically seen; 28.5 inHg and 29 inHg indicate less vacuum than 29.9, meaning the system hasn’t reached as deep a vacuum. So, 29.9 inHg is the best indication of a good vacuum.

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