Suncourt ZoneMaster Fully Adjustable Motorized Airflow Control Zone Damper, UL Listed 24VAC/20VA Plug-in Transformer Included, Compatible with Any 24 Volt Thermostat, Normally Open – 8", Silver

Good product

This really works. Mine is in the attic, and I can't hear it at all from the 2nd floor bedroom just below it. The design uses a motor (not a solenoid) and has "lost motion" so the motor runs a few seconds before the driver bar actually engages the baffle. See the video for timing. You must leave power applied as long as you want it in the powered state... a spring drives it back to the starting position when you remove power.The motor gets very warm to the touch, but not dangerously hot. I measured the power draw and temperature but that was long before I wrote this review... maybe 10 W and 105 deg F? I'll update this review if I climb back up there and retest.I recommend using a power switch or plug with a built-in timer so you don't accidentally leave it in the actuated position all day and make your bedroom so hot the wife notices. Oh, and make sure you use plenty of foil hvac tape to avoid air leaks.Note: this design is either all-on or all-off... the design isn't amenable to driving the motor to a different position each time based on temperature measurements in the room.

The damper works well, but be sure to read the item description to understand what power supply is being shipped with it. The picture shows a wall plug type of power supply, but the description says that it has a hard-wired power supply. The description was correct, so if you're expecting a power supply like what's in the picture, keep looking until you find the correct one. Otherwise, you can purchase a 24v power supply for sprinkler systems on Amazon that will work just fine. Overall, the damper does the job, but it does require some modification if you want it to perform the best. The foam weatherstripping inside the damper that creates a seal against the damper itself is not installed well, so it leaves a gap when the damper is fully closed. That gap allows air to leak by, and can also cause whistling noises. I purchased some weatherstripping from my local hardware store and fixed the issue before I installed it. Now it fully closes off the duct when it's closed. Overall, I'm happy with it, but the need to replace the weatherstripping is why I give it 3-stars.

I haven't installed these yet and therefore haven't used them but I did wire them up and test them. After some needed modifications right out of the box I think they should work fine.I bought three of these 8" normally open. On all three of them, when the damper was fully closed the damper did not seal with the foam seal properly. There was anywhere from 1/4" to almost 1/2" gap between the foam seal and damper. I was concerned with a gap, there would be a whistling sound due to the air flowing through the gap when the HVAC was on and the damper closed. I ended up pulling off the foam seal, applying some rubber cement and moving the seal into a better position that created a proper seal between the closed damper and the foam material. Now there is no gap. It wasn't much work to do it and I think it'll hold but no product should need modifications right out of the box to work properly.

Dudes! I hands down could not survive without this most awesome of all dampers. It saved my relationship with my gf. My dog likes me again! I highly recommend it