Well I don't either...not one I can get into. However, there is a space where the HVAC ducts and wiring. If you have a light fixture you are set. Turn off at breaker, unscrew fixture and drop down from ceiling. Unscrew wire nuts, and screw back on the hot wires. Stuff them back into hole.
The hole is probably 4". I got a plastic 2 piece collar meant to be able to easily disconnect the dryer vent from the wall. It fits perfectly in 4" hole.
It was less than $10 from home depot, but could rig another way.
It will really help remove heat from room, the vent tube even feels hot. Fix one problem and create another...the odor can now permeate the house and every once in a while get a light whiff only a smoker would recognize from under the house. I use a twist up air freshener or two under the house and the problem is gone, and a lysol disinfectant timed sprayer near the door in laundry room for the odor in the house.