Have owned my Integra II Inert since 2008, have v 1.33 software, stove is installed correctly. Cleaned mostly by the book. Been burning Bear Mountain pellets since day one and never had an error except for when I run out of fuel and get an ER0. This year I bought a few bags of something other than Bear Mountain that claimed to be premium, just to get me by the first few cold nights. Not one bag in I had an ER3 (air flow error). Just goes to show that fuel does matter. Not asking for any advice, just letting everyone know that what you burn matters.