Product review (5 stars): Awesome simple means for us to save and be more energy efficient, especially living in a more drier, less humid climate
First this is best for dry climates and only electric clothes dryers. for the past few years i have bit by bit made our home more energy efficient. i do so for both the long and short term benefits. a few weeks back when it was -20F i happened to walk by the outside vent to the dryer and felt all the hot air just going out and being wasted. i thought somebody must have come up with an idea to trap, save and make use of that warm air. after looking at several i finally decided on this one. it has a simple basic design and works fantastic! it arrived two days ago. i forgot to order an extra 8' section of the exhaust hose (makes the install much easier) so i buzzed into town, came back and was good to go. you might pick up two extra plastic ties just in case. they cost very little but good to have on hand.

make sure when installing that the "in" side and "out" side are connected properly and not reversed. i did one extra thing myself not in the instructions. the "flapper" inside has a small round hole about the size of a half dollar. i don't want part of the hot air coming inside i want it all. so i put a strip of gorilla tape over it so no more doughnut hole.

the first time we ran the dryer you could tell immediately that it was working. the entire house smelled like fabric softner sheets, like you'd sprayed the place with fresh linen scent febreeze. you can feel the humidity but for us that is good as often we get in the single digits for humidity. you must ensure NOT to close up your laundry area when drying clothes. if you do all that hot humid air will just fill your laundry room. then rather than saving you money it will cost you. your dryer will have to run longer and harder to dry clothes with all that extra moisture in the air. the hot air will have no means to circulate in the larger household.

i have my "heat keeper" vent on the wall placed at chest level and aimed directly at the doorway so the hot air goes where it should. this is such a simple yet awesome idea and i am so glad for that one -20F degree day or i'd never thought about doing this.