One thing I know is having a vent stack can be key to improving air flow. I'm going to buy a 3 foot length of PVC pipe which is bigger then vent on top, between adding that it may be enough to pull consistently through the grease drain hole. If that doesn't work; The other option would be, if your not going to use the wood chip adding tube is pull it out and cram a piece of foil in the hole but leave it open by about half the hole size. Keep in mind I haven't tried this yet but I will this weekend, this idea it is knowledge gained from working with other wood burners. Nothing like a 3 foot pipe on top to get a good draft.I have been experimenting with the AMZN 6 tube in my MES 30. I've found it works great on the lowest rack on the left,vent wide open. I leave the chip loader half out. I love Todd's products. It's like having a new smoker.