I spoke with Woodstock last night about the catalytic combustor in my PH. Since I am burning some 'not as favorable' wood I have been struggling with the cat firing at lower temps. When I called, Jamie sent me the attached file on how to 'deep clean' the catalytic combustor on their stoves. I plan on doing the 'deep cleaning' sometime over the weekend when we get some warmer temps. I'll let you know how significant of a difference it makes.