I have a 1905s era efm 520. Replaced my feed tube this year after the other corroded. My 55 gallon metal drum is only about a foot from the boiler. I am getting constant blow back into my hopper drum. Feed tube/pipe is hot and this is sending fumes and co into the house. It is also quick drying the coal and causing sulphur smell. I have cleaned the holes on the feed pipe repeatedly, lowered the air flow, had the chimney cleaned a serviced. Draft is good for main fire chamber and for my oil boiler that serves as a back-up. I just can't solve the problem. Went away this weekend and came home to CO detectors going off and strong odors in the house. I can smell that it is coming form the hopper and where the feed pipe enters the hopper. I noticed a week ago that the metal hopper had corroded under the feed pipe and there were several large holes. I thought that was the problem so I patched them. It ran fine for a few days then back to crap.
Any ideas? I plan on replacing the hopper with a plastic drum/trashcan. Should I extend the auger and feed pipe further from the boiler? Never had that problem the last 2 years. Should I keep a lid on the hopper? Is there some other thing I am missing? Thanks for the help.