Hi, I have a Vermont castings encore 0028 that I recently rebuilt. New gaskets, lower firewall, upper fire wall, refactory assembly, and a new condar catalytic combustor. I have read both the owners and service manuals from front to back and I'm positive I rebuilt the stove properly. On my first burn everything work great. Stove was brought up to 500+ degrees and I engaged the by-pass. I quickly noticed the temperature continue to rise which tells me the combustor was doing it's job. I then lowered the thermostat all the way and continued to burn at 550-650 degrees for the next 5-6 hours. Fast forward to my next burn. Did everything the same as my first burn and when I engaged the by-pass at 500+ degrees I noticed the temperature started going down. I have had an addition 2-3 fires and still can't get the combustor to work properly. At best, when I've been burning for an hour + and engage the by-pass the temp will stay the same, but never go up. Any suggest would be greatly appreciated.