It appears to be some kind of heat storage system. In the same room it had a control with two knobs, pne labeled (setback" and I think the other one was just temperature, like a thermostat. Anyone know for sure what it is?
I turned up and heard a fan running but no hot air came out although it seemed to be pulling in cool air. This was in a south-facing room with big windows. Cound this thing be pulling air out of this warm room, running it through thermal mass to store heat, then pumping heat into into the cold downstairs?
Picture’s not too good. Last picture this camera will ever take