Is your stack temp. higher than normal? Easy check here--don't know how the EKO bypass damper in the top chamber closes but.....creosote or possible loose hardware (happened to me before on my ECO) will prevent the damper from closing completely. Can you close the damper while the top/loading door is open? If not closed completely it will allow your fan to blow everything out the top and you'll never get the full out gasser flame in the combustion chamber. You'll get the lazy flame in the bottom and it'll take forever to get up to temp. Open the loading door and close the bypass if you can to check it out.