This link goes to MILJOCO Gauges in Mt. Clemens, Michigan
I must thank the company for having this on their website.
We deal with -4.0, -8.0 and -12.0 inches of water column when testing evap systems.
EG; -1.0 inches of mercury is equal to -13.6 in-H2O.
Engine intake vacuum is typically -18.0 inches of mercury.
Some people are comfortable with different SCALES and this will convert a value you may have measured to a scale you're familiar with.
HTH.
I must thank the company for having this on their website.
We deal with -4.0, -8.0 and -12.0 inches of water column when testing evap systems.
EG; -1.0 inches of mercury is equal to -13.6 in-H2O.
Engine intake vacuum is typically -18.0 inches of mercury.
Some people are comfortable with different SCALES and this will convert a value you may have measured to a scale you're familiar with.
HTH.