Vokoun made 21 saves in the first two periods before sitting out the third because of a sprained wrist. Darcy Hordichuk, Alexander Radulov, Marek Zidlicky and Shea Weber added goals for the Predators.
Vancouver backup goalie Dany Sabourin gave up five of the six goals. He was benched at 12:37 mark of the second period, with Roberto Luongo playing the rest of the period. Sabourin returned to play the scoreless third.
The Predators took a 2-0 lead in the first 4:31.
Radulov struck first, skating through the slot and putting the puck over Sabourin's glove at 2:43. Hordichuk followed with another shot high to the glove side.
In the second period, Nashville scored four goals on nine shots.
Hartnell found the net twice, first on the power play at 10:09 when he posted up in front of the net and put the puck high to the stick side.
At 12:20 Zidlicky skated in from the right side into the crease area. Sabourin got a glove on Zidlicky's shot, but couldn't control it as the puck bounced out and across the goal line.
Seventeen seconds later, Hartnell scored his second goal of the game, again standing in front of the net as he pushed the puck past Sabourin.
At 16:20, Weber scored on the power play with a slap shot from the right point, the only goal given up by Luongo.
Notes: The Predators have not allowed a power play goal in their last three games. ... Nashville's Paul Kariya assisted on three goals, giving him eight points (one goal, seven assists) in his last six games. ... David Legwand was credited with an assist, giving him six points (three goals, three assists) in his last six games. ... Vancouver is 8-3-0 against Central Division opponents this season.