It certainly does a lot better job at removing cooking smells with the vent open. I don't always open ours, but if it is closed and I try to run the fan on a higher setting, it puts a lot of strain on the motor, and it gets hot enough to smell it.
Ellen - Navigator
Boyd - Driver
09 VF35CK (Gone)
We have a truck, it pulls a 5th wheel. We like to camp with full hookups and go for day hikes with our dogs.