M18 under sink exhaust fan


I just noticed that my 2012 Edge M18 has an exhaust fan under the kitchen sink.. it's kind of hidden behind stuff so I never saw it before. It has an electrical wire connection, but I have no idea how to actually turn it on. I don't see a button anywhere.. does it turn on automatically when I turn on something else? I figured that it was there because of Grey water tank fumes that can come up.. but no idea how it is actuated.


Staff member
I've never heard of an exhaust fan under the sink. Are you the original owner?
There is however, a passive air admittance valve located there. It does not require power.
If you smell sewer gasses there your air admittance valve may have failed. Easy to change and inexpensive. Least expensive would be similar to what you have and cost a few dollars. The brand name, Studor, is around $20.