So I read my M55 Technical manual/"A Fresh-air kit is recommended for all installations. Failure to install air may result in improper combustion as well the unit smoking during power failure" Naturally, Enviro wants to cover their legal butts..but I would have to think that the above statement is a true one. Because my wife ( me too) will freak out and at least be very upset if we get smoke in the house, a UPS is on the front burner as well as an OAK install. Today I went to my dealer for his opinion on the OAK and then a 20 year wood/coal/pellet veteran who is well past his eyeballs in installs to the point where I don't know if he and his other install person can help me. The old veteran says "whenever possible, any pellet stove should have an OAK....and your model is no exception and it will improve your overall heating of your house (temp and draft) It will produce a better combustion and help in in the reduction of smoke in the house. He asked me if the liner that the dealer put up my chimney was insulated? I said, No it wasn't! He said that is mistake number two. He said your liner, even if cleaned yearly will not last anywhere near as long as an insulated liner. He did however, say that as long as you run your stove on heat 3 or higher you should be OK! Creosote isn't much of a problem on the higher temps, just never run your stove on low, your creating cresote and making your stove dirtier sooner than need be. He was not as positive on his coming out to do a mag check. (this guy is very old school) He said the mag gauge should really only be used to detect blockages in the exhaust. He says "you need to learn your stove, every stove is different house to house, every pellet is different, you need to experiment, it's like learning how to ride a bike." Personally, I would like to know what a gauge says...SO then, I go to my dealer and talk to the person who has all the knowledge about my stove. I mention an OAK and I am told, it can't be done! I then take my M55 manual out of my pocket and show them the advice from Enviro.....and the response is, "and how would you propose this be done?" So after I told this person about basically going straight out the chimney, the person replied back....."Your crazy and do you know that even if you did put an intake duct on it, that inlet only takes in 30% of the intake air? and it won't have any effect on reducing smoke if the power goes out"........at this point, my phone went off and this person turned to help a customer and I left wondering how the stove sucks in the other 70% of the intake air??? Sorry for the long post, but I want to get some more feedback! Thanks, Bill