This is my first, a classic UDS build; straight, no chaser. Seems fairly air tight. 14"x24" fire basket, caps and ball valve vents. Two 1" ID chimneys.
I can take the fire up or down at will, so air control doesn't seem to be the issue (I think). Doing the test burn, and my temp creeps up (maybe 1 deg every 5 mins) or down, can't seem to get it to lock in. 2 out of 3 vents closed, just working the ball valve, 70-60 deg ambient temp/60% humidity on the test day. I'm giving 20-30 minutes between adjustments.
So my question is what should I realistically expect as far as temp stability:
- Dead nuts on the temp for hours, +/- a couple of degrees
- The gradual delta I'm seeing?
- An over/under fluctuation of 30/40 degrees? (I guess this is not mutually exclusive from the former condition)
Any guidance would be greatly appreciated.