The installer of your pump is a professional WHO can read directions.
You lucked out big time.
You see a lot people install a sump pump with a check valve with total disregard to good pumping practices.
The expert who did install your pump knew enough to drill a small hole BELOW the check valve to break the vacuum after the pump finishes pumping and allows the check to reset properly.
I am impressed someone still reads installation manuals and codes.
[Edited by Moderator on 18 March 2001]