Keen Home Vent - Ceiling Register Grilles

thingiverse

The Keen Home controlled HVAC vents are excellent, but have a flaw for certain homes: the register covers do not work at all well in ceiling-mounted registers. The stock grilles do not work well in the ceiling because: - They are designed to distribute heated air laterally in a room from floor mounted registers, since warm air rises. As a result they mainly heat the ceiling when mounted in a ceiling register. - They are designed for strength and appearance, rather than airflow - the vanes are too thick and too close together to pass a lot of air - much less than the metal register grilles they replace. - They are designed to send all the air diagonally in two directions toward the same long side, which diffuses nicely from a floor vent, but if you use them in the wrong orientation, they will mostly heat the nearby wall. These are two printable replacements: one for the 4x10" Keen Vent, and one for the 4x12" size. Each is designed to a) maximize airflow, using fewer thinner vanes to block less airflow, and b) to direct it downward straight out of the grill, in order to direct warm air down into the room and mix it with the rest of the air in the room, rather than distributing it horizontally up near the ceiling. In the photo, the original Keen grille is at the top, this replacement at bottom. Note that the vanes are asymmetrical and point the air toward the short ends, so you can direct more heat toward the colder side of a room, or balance the flow by reversing the grille. Also worth noting that these vent covers work well for floor-mounted registers for air conditioning, as they would send the cold air upward to mix with the room, rather than down near the floor.