Safety
If you reeeeeally want an opinion, ok. The manufacturer designed the blower to be operated below 16"hg(ish) pressures, under a load, in an enviornment that provides reasonable ambiant cooling.
You already know that an increase in hg results in more heat generated within the blower. At 19"hg or above I believe you are at or close to the outside of the envelope.
At 15" my hose cuff will tug on my clothing very aggresively and boy how it will grab hold of curtains and bedding like there's no tomorrow. Is anyone giving much thought to how much potential energy there is in a 2" cuff pulling at 19"hg+ ? If insurance people ever did an audit for up to date potential liability I betting we would see a change in our premiums.
But, not to rain on the
Vortex parade and it's a big parade indeed. I hope there is a big safety discussion that comes with the machine.