Higher draft settings produce more heat-- more air=more fire=shorter burn times. But draft settings above ~2 become inefficient. The smoke passes through the cat so fast it doesn't fully burn. This shouldn't be a concern because the stove will reach max stove top temps at around 2. Lower draft settings--less air=less heat=longer burns. Most people burn around 1. It will depend on the outdoor temps, sqft heated, insulation, wood species, indoor temps, etc.
Cat stall- picture a match going out. The cat will not relight until the smoke reaches ~550
![Fahr ::F ::F](/talk/styles/default/xenforo/smileys/f.png)
, remedied by the same steps taken to light the stove- open bypass, get the temps up, re-engage cat (close bypass), set draft. Most of the time I can glance at the stove from my chair and see a cherry red cat, so I know its working. But the cat doesn't always glow when working. Earlier in the burns there is more off-gassing/smoke and the cat is more active. Later in the burn less so. If the cats not glowing a look at the stove top temp (STT), if its above 250 you're good. An infrared thermometer will also show a hot spot right above the cat, cooler off to the sides when its active.
Its not as complicated as it sounds. If you have any questions you've found the right place and Woodstock is a phone call away. When you call them, you talk to English speaking people that know their products, most have them in their own homes. Have you read the manual yet? It is written very well. Also Fireview and Keystone operate very much alike and there are many threads about burning the FV. The main difference seems to be, the FV can have very high (over fire) stove top temps when the draft is set to 0, seems counter intuitive but the stove top gets very hot above the cat due to lack of fresh air flow. I've burned at 0 often and never had any problem. The Keystone has a 1/4 inch air inlet hole on in the ash behind the ash pan that the FV doesn't have, probably why 0 burns are fine (at least for me, never heard from any other KS owners about the issue).