What dis?

Just moved into a house that's roughly 7 years old. I didn't get to speak to the original owners. There is an intake screen in the ceiling of the kitchen (there's also an exhaust over the stove that does exhaust direct outside). Inside appears to be a gated air manifold. The whole thing seems to be tied to a Honeywell timer/switch. What is this for? I assumed it recirculates into the house HVAC, but maybe not? Ideas?