Official KitchenAid downdraft ventilation system parts

Most common KitchenAid downdraft vent parts that need replacing

• Gear motor. The gear motor raises and lowers the pop-up vent when you push the activation switch. Limit switches shut off the gear motor when the pop-up vent reaches its destination.
• Grease filters. The grease filters are aluminum mesh filters that trap grease suspended in the exhaust. The grease filters attach at an angle inside the vent opening.
• Limit switch. The limit switch detects the position of the pop-up vent and stops the gear motor from operating when the vent reaches the full up or down position.
• Up/down switch. The up/down switch on the right side of the pop-up vent starts the gear motor to raise or lower the pop-up vent when pressed.

How to fix your KitchenAid downdraft ventilation system when it goes up and down continuously

Problems with the vent limit switches or the up/down activation switch can cause the downdraft vent to move up and down continuously.

Limit switches detect when the vent reaches the upper and lower travel limits. If one of the limit switches breaks, the vent will raise and lower continuously. Disconnect electrical power to the downdraft vent and test continuity through the limit switches using a multimeter. Replace a limit switch if you measure the same continuity through a limit switch when the switch is activated and deactivated.

If the limit switches are okay, check the position of the up/down activation switch with power to the downdraft blower still disconnected. The vent must be in the raised position to check the activation switch, so lift the vent if it's in the down position and tilt it slightly so it stays raised. Remove the switch cover from the right end of the vent. Check the position of the up/down activation switch plunger. If the up/down button pad constantly presses down the plunger, loosen the up/down activation switch mounting screws and move the switch down until the bottom of the button pad membrane barely touches the plunger. Tighten the up/down activation switch mounting screws and replace the switch cover.

If the up/down activation switch position is okay, check continuity through the switch using a multimeter with electrical power disconnected from the downdraft vent. If the meter measures near 0 ohms of resistance with the switch plunger released, replace the up/down activation switch because it's letting current flow to the vent gear motor constantly, making the vent constantly move up and down. The up/down activation switch should stop current flow to the vent gear motor when the up/down activation switch plunger is released.