My Acentra 52i insert was manufactured in May, 2014 and installed In September, 2014. I started running the unit in room temp mode when it was in the 40s outside and it maintained a room temp of 74 degrees with a setting of 75 on the dial and a burn rate of 4. I have an OAK installed. The Accentra is located in a large cathedral great room with 17' ceilings (large ceiling fan is set to low and in reverse) and my home is all open concept with a second floor that has an exposed staircase to the second floor. My total square feet of space to be heated is 2800. The temp probe is on the opposite end of the room approximately 25' away from from the unit at 5 feet off the floor on the wall. Once the outside temp dropped to the low 20s, all bets were off. The unit seems to be blasting away with full flame and room distribution blowers blowing on full mode; however, it can't get the room temp above 65. I just don't get it. Also, unless I put the unit on stove temp at 7 and the feed rate at 6 (maxing everything out) I only get a 3" ash bed. If I set everything at the max rate, I will get the 1" ash bed. I NEVER get unburned pellets in the pan. I religiously clean the entire unit every two weeks as well. I take everything out and vacuum all of the ash out. The only thing I don't do is pull the entire unit out from the fireplace. I already had the tech out and he said that the unit appeared to be operating just fine and then charged me a fee because there was no warranty work to be performed. I just don't know what to do. I really wanted not to use my propane fired central heat system this winter. I am using LG basic and LG premium pellets. I also have the LaCretes as well. I could try just using the La Cretes and see if they make a difference. The unit heats my entire house when the outside temp is in the 30-40s. It keeps the downstairs at 72 and the upstairs at 74 with settings at room temp at 75 and a 4 burn rate. I always leave the blower setting on high. I honestly could care less how many bags of pellets I burn because it is still cheaper than propane. Is something wrong with this stove, or I have I just maxed out the ability of this unit in very cold weather? Any suggestions would really help.