Navac vacuum pump user manual.

As with all brand vacuum pumps, proper storage and maintenance of our tools are important.

Test the function of the vacuum pump using hoses rated for vacuum, use a micron gauge to verify accuracy of another micron gauge.

Test your manifold gauge set for vacuum and pressure leaks prior to testing for system soundness. 

Knowing the tools you are using are properly maintained and accurate, will save you HOURS of looking for problems in a system, when the problem may be with your tool.