Hello , We are new to the forum .As of this fall , new to pellet stoves .Yet have watched , researched and have been Learning . This is our 3rd stove .We did not have great luck with the Englander .Auger issues ( way to many) .We then went with the Pelpro Cast Iron TSC90 , which was great for a month .We had one problem after the other with the Thermostat , fans ect .The Pelpro CS was horrible .We returned the stove . We cleaned them and cared for them as directed and more if needed .After much looking , We chose the Serenity .We will need a second one in this 2 1/2 story 1847c Old Victorian .Yet we wanted to see if some fan noise is normal .or an issue we need to deal with CS or maybe answers here .The stove seems to be running perfectly /As we learn it and play with the settings. The noise is weird . constant and changes pitch with higher setting . Its not really a whine,but an annoying pitch sound , I cant explain ( being female it reminds me of a hair blow dryer on hold ) I am not sure what Murph would call it . He is mechanically inclined and all looks good as he went over it . Just seems to change if he lightly blew on the fan LOL Any advice would be awesome . CS Isnt open until Monday . Thanks V