If you have an atmospherically vented water heater that vents into your chimney and have recently had your furnace replaced to the direct vent type thus orphaning your hot water tank exhaust in the chimney flue, you need this to prevent backdrafting in colder climates. Backdrafting happens when the exhaust gases from an atmospherically vented water heater spill out into the room, rather than safely leaving the house through the vent. Exhaust gases contain carbon monoxide and high levels of moisture, so this is always a condition that should be corrected.

Before installing this, at temps below freezing, my water heater would backdraft for 5-7 minutes until the chimney flue would warm up enough to draft the exhaust gasses properly. With this installed, it kicks on as soon as the heater turns on and induces a draft immediately. I have not had any backdrafting issues since installing this.

Bonus, it's quiet (watch the video, you can actually hear my 2 y/o squealing upstairs in our family room)...It's directly beneath our family room and I cannot hear it running from upstairs. FYI this took me about 2 hours to install and I really took my time...

There's only one con in my book, it's expensive because it's the only product of this type out there.

works as expected, but pricey. Would like to see others make a similar unit so cost would be more reasonable. good safety system for backdraft! they should sell that separate for peace of mind!