I had a thread a few days ago. Timing was such that we did not have much leeway on how long before the fire was going good, cat engaged and stove final set so we could leave and forget it. If memory serves me it was just a tad under 40 minutes. Our normal times run from about 35-45 minutes. I've done it faster and I've done it slower, but would guess that 40 minutes is about average.