Vale largely dominated the clash at the Globe Arena but Charnock struck with a rare goal to hand Sammy McIlroy's a hard-earned 1-0 victory.
The centre-back, on loan from Torquay, said: "I can't remember the last time I scored but I'm delighted it got us the win.
"There's enough quality here to get out of trouble.
"Hopefully we can now build on that and push up the league."
Source: PA
Source: PA