Turned out to be dirty flue pipe and ESP probe....producing 6 blink error & pellet overflow.

Pellet stove pipe is a double-walled pipe that is very similar to B-Vent pipe. The major difference in the two, is that pellet stove pipe (L-Vent) has a stainless steel inner liner, whereas the B-vent has an aluminum liner. There is a special connector that hooks up to the stove (made by the pellet stove pipe manufacturer) that is designed in such a way that the inner wall of this adaptor goes into the inner wall of the collar on the stove, thus assuring a tight, non-leaky fit. There is a possibility that the installers did not use the proper connector on the back of the stove exhaust. If that is the case, then yes, you may be getting some spillage into the room. If you have some "give" in the pipe at the stove collar, I would disconnect it and see if it is fitting tightly. Also, check to see if the gasket is missing from between the two liners (it looks like a soft piece of rope). If it's not fitting right, I would call the installers back and make sure they used the proper stove adaptor with the gasket. Now, some models of stoves do not need this special adaptor. On these stoves, any length pipe will fit snugly without the stove adaptor, but still needs the gasket (the gasket is installed with each piece of pipe). I cannot remember if the P68 needed the adaptor when Dura Vent brand pipe was being used. Some models of Harmans needed it, some did not. My opinion: The problem is in the installation and not the stove.

You might be able to push longer vertical distance by using 4inch PL vent pipe rather that 3inch. The less bends, the longer the pipe can be but I don't know exactly how high. I know the Accentra is 20 feet for 3inch and 30 feet for 4inch. I'm not sure with the P-68 because of the output being in the back and not the top. A horizontal ouput and T will reduce overall length. I would check with the local Harman dealer for the info.

My Harmon P68 is a piece of junk! My first stove was an Englander, a cheap pellet stove purchased at Home Depot. The Englander worked great. My Dad got one after seeing mine, his works great. After using the Englander I "upgraded" to a Harmon P68, that was a mistake. I saved up $3500, got rid of the Englander, ordered the Harmon P68 in Dec 2010, installed it in Jan 2011. After installation the feed motor needed replacing. So I couldn't use the stove for a week. Harmon sent the wrong part so I had to wait an additional week. The Dealer/installer was apologetic and not happy. I was starting to regret this stove swap. The stove worked great after that. Fast forward to Feb 2012. The blower motor is making a thunking noise and occasionally screeches like a train whistle. The warranty has expired. Remember, I ordered it in Dec it was installed in Jan and it didn't start working until 2 weeks after installation. But it's a week and a half since its first firing and Harmon doesn't want to fix it. The Dealer/Installer is an older guy that's been selling and installing stoves for 25 years. He's seems as upset about this as I am. He told me Harmon used to back their stoves with a longer warranty but another company purchased the name and now it's just 2 years. He also said he used to be proud of the Harmon stoves because they used to be built better. He said the original stoves used to go 5 years or longer before needing motors replaced. He told me that he's done with Harmon. Probably feels a little guilty that he didn't tell me this when I purchased my junk Harmon. So I'm going to replace my blower motor, the 2nd stove motor in 2 years. And I'm going to start saving up for a new stove. Not sure which brand but it won't be a Harmon. If you want to pay an extra $1000-$1500 for a name on a stove that might or might not work out of the box. That'll probably need expensive repairs and replacement parts soon after the warranty expires. Go ahead and buy the unreliable Harmon P68! It looks nice but it won't heat your house.