So the new Coolant System Pressure Tester is assumed not to work correctly?
nothing wrong with verifying it against another one.
especially if you are buying the HF one.
there is never anything wrong with verifying/calibrating any tool, new or used.
i figured guys wouldnt get what i was reiterating from my freind.
he is a professional car prep guy in the formula sports car community who has helped me quite a few times when i was not able to fix my car.
he said just because something came in a box( my new replacement part), it doesnt mean that it works( dont assume). a used part that has already been tested is known to have worked correctly. thats all;
its part of the troubleshooting process.
i am just trying to be helpful to the original poster, and maybe help you as well.
carry on