How do you do that door puzzle in the basment of draynor manor?

Heres how to do the whole quest.

Veronica

Talk to Veronica at gates of Draynor Manor. She wants you to find her fianc�e Ernest. Her fiancee went into the big spooky manor house to ask for directions. An hour later and he's still not out yet.

Ernest

You find him in the top floor of the mansion, but he has been turned to a chicken! Help the professor to turn him back to human.

Rubber Tube

Take spade from 1 of the rooms and go dig compost outside the mansion (west side). You find a key. Use it on the locked door inside the mansion.

Oil Can

Search the bookcase in the room with the red carpet on the ground floor, and you will find a secret entrance to the next room. Go down the ladders. You need to pull right levers here to get the Oil can. If you really want to ruin the fun, heres the right combination.

The levers

Pull A, Pull B, Go northeastern door, Pull D, Go southwestern door, Go southern door, Pull A, Pull B, Go northwestern door, Go western door, Go northern door, Pull E, Pull F, Go eastern door, Go eastern door, Pull C, Go northwestern door, Go western door, Pull E, Go eastern door, Go southern door, Go southern door, Go western door

Pressure Gauge

Take fish food from 2nd floor. Take poison from witch's room and use it with fish food. Go outside and use the poisoned fish food on fountain. Search the fountain.

Professor

He turns Ernest back to human after you bring the items he needed.

Reward: 300gp

Quest points gained on completion: 4