I think Rob has asked a lot of good questions, and I agree the usage rate doesn't look that bad under the circumstances. I also agree with Rob that the timer settings may have been contributing to the incomplete burn.
markviii wrote:If 4.5 air gives you a good burn, leave it there. As for the draft, as long as you have negative draft at the firedoor -0.03 at the flue will work. I also would change the timer to run the stoker for 2 minutes every 30 minutes, that is EFM's recommended starting point.
Where do you live?
Does your EFM have an insulated jacket around the boiler?
Is the garage heated?
How well insulated are the lines?
Do you constantly circulate between the EFM and the house?
My thoughts are that if you have an uninsulated boiler running in an unheated garage, and you are losing some heat underground, 160 lbs per day is not impossible for heating a 3,000 sq. ft home in cold weather. As a means for comparison, do you know how much fuel/propane/wood/whatever it took the heat the house previously?