New to Coal. Sulfur Smell With Harman Magnum

Hi,
I'm new to this forum and to burning coal in general. My wife and I recently purchased a new home and along with it came a Harman Magnum coal stoker in the finished basement. At least from what I've been able to find online I think it's a Harman Magnum. The only other form of heat for the house is electric ceiling heat so I'm hoping I can get this stoker working correctly.
Anyway, the weather started cooling off as it inevitably does in PA in October so I fired it up for the first time. After the first night, we woke up to the whole house smelling like sulfur. So I shut it down and started investigating. Everything I searched on google led me here.
The first thing I did was remove the flue pipe and inspect the chimney. This is what I found in the flue:


So I replaced the entire thing with black stove pipe from Lowe's.







After that, I fired it up again. Much better results this time, but still every once in awhile I'm getting that sulfur smell in the house.
The chimney is completely clear, no blockage whatsoever. Much cleaner than I expected after what I found in the flue pipe. It's a brick chimney with a clay liner. 8" round pipe through the wall to I believe and 8"x8" square clay liner. It's about 20-25 ft high. I'm just trying to provide as much info as possible.

My questions are:
1. Barometric Damper. I found a manual online for the stove and it recommends a Barometric damper. This seems to be a controversial topic on here so I'm interested to hear everyone's thoughts.

2. Sealing the pipe joints. I used a product called Fire Block from 3M around the base of the pipe where it enters the stove. Do I need to do seal each joint? I used sheet metal screws on each one.

3. Outside Temp. Does outside temperature play a role in how well the stove gets a draft? Should I only be using it when its a certain temp outside or below? It seems like the smell is happening more often when it gets a little warmer outside. Right now its the only form of heat in our finished basement but I'm working on some electric baseboards to use on days when I don't need much heat.

4. Is there anything else I should be doing? I replaced both seals around the fire door and ash door, cleaned out the grates and vacuumed all the fly ash out of it that I could find. I replaced both electric blowers on the back of the unit because one was squealing and the other rattled like crazy. Are there any other seals I should be inspecting?

I have a brand new carbon monoxide detector right at the steps to the upstairs. Our house is a split entry. I order a detector with a digital readout so I know exactly what the levels are.
Any help is greatly appreciated. Winter is right around the corner so I want to get this thing working.

Welcome to the forum.....

Check how far open the baffle plate is on the combustion blower intake. It should be at least 1/2 way closed.

There is probably more air going into the stoker via the combustion blower than the flue pipe can exhaust and it is being pushed out the stove into the living space.

Good job cleaning the chimney and replacing the flue pipe. It's good to start with a nice clean install when you are going through the learning curve.

fastlane4,Welcome to the forum. If you would fill out more info in your profile like your location,maybe a member is close enough to you & could stop in to help you,just never know. Barometric damper is highly recommended for your unit ,But you also need either a Magnahelic or Manometer to monitor the draft & see if there is a low draft issue. I bought 2 used Magnehelics from Moses B. Glick.com for $53 shipped to my house. Cat # 2000-00. I am not familiar with your Harman at all.

titleist1 wrote:Welcome to the forum.....

Check how far open the baffle plate is on the combustion blower intake. It should be at least 1/2 way closed.

There is probably more air going into the stoker via the combustion blower than the flue pipe can exhaust and it is being pushed out the stove into the living space.

Good job cleaning the chimney and replacing the flue pipe. It's good to start with a nice clean install when you are going through the learning curve.

Where is the baffle plate located?

windyhill4.2 wrote:fastlane4,Welcome to the forum. If you would fill out more info in your profile like your location,maybe a member is close enough to you & could stop in to help you,just never know. Barometric damper is highly recommended for your unit ,But you also need either a Magnahelic or Manometer to monitor the draft & see if there is a low draft issue. I bought 2 used Magnehelics from Moses B. Glick.com for $53 shipped to my house. Cat # 2000-00. I am not familiar with your Harman at all.

I was planning on purchasing a manometer if I need a barometric damper. I don't know much about the dampers yet but I'm trying to do some reading and learn how they work. I updated my location. Thanks

Your mag stoker has 2 fans in the back. One is the combustion blower. It's on the side of that fan where the air is drawn in. It looks like this. Yours should probably be closed more than the one in this pic.

See CK's pic, it is a metal plate that closes off the intake of the combustion fan by rotating about a single screw.

A little more info....

A barometric damper is not going to help you now, when the temps are on the warmish side you want as much draft as possible coming through the stoker. I have a baro and on the warmish days I cover it with foil to maximize my draft through the stove to keep the exhaust heading up the flue pipe. A barometric damper helps limit the draft through the stove to a stable level so you don't have wind events and extreme temps pull the heat up your chimney.

Outside temp will play a role in draft. You may need to keep combustion fan baffle plate closed a little more now in the shoulder months than in the dead of winter when it is real cold out. A manometer installed in the flue pipe would let you see the draft number.

It wouldn't hurt to seal the pipe seams. The important part was using the screws to secure them.

Good job replacing the gaskets and cleaning the grates. Use a hand held drill bit to make sure the holes are cleaned out on the grates.

Make sure you put the correct fan into the correct slot. I am going by memory so the exact numbers may be off, but the combustion fan is about 65cfm and the distribution fan is about 150 cfm. If you have them backwards you would be blowing way too much air into the firebox. I don't remember if the flanges are different sizes to keep you from putting them into the wrong slot or not.

How wet is your coal? Damp or wet coal will cause the same symptoms .

titleist1 wrote:See CK's pic, it is a metal plate that closes off the intake of the combustion fan by rotating about a single screw.

A little more info....

A barometric damper is not going to help you now, when the temps are on the warmish side you want as much draft as possible coming through the stoker. I have a baro and on the warmish days I cover it with foil to maximize my draft through the stove to keep the exhaust heading up the flue pipe. A barometric damper helps limit the draft through the stove to a stable level so you don't have wind events and extreme temps pull the heat up your chimney.

Outside temp will play a role in draft. You may need to keep combustion fan baffle plate closed a little more now in the shoulder months than in the dead of winter when it is real cold out. A manometer installed in the flue pipe would let you see the draft number.

It wouldn't hurt to seal the pipe seams. The important part was using the screws to secure them.

Good job replacing the gaskets and cleaning the grates. Use a hand held drill bit to make sure the holes are cleaned out on the grates.

Make sure you put the correct fan into the correct slot. I am going by memory so the exact numbers may be off, but the combustion fan is about 65cfm and the distribution fan is about 150 cfm. If you have them backwards you would be blowing way too much air into the firebox. I don't remember if the flanges are different sizes to keep you from putting them into the wrong slot or not.

Ok, progress already. The reason I was confused on the plate is because there isn't one. Neither fan had one when I replaced them. Both fans on it were the same when I replaced them. I have no idea if they were original or just something the previous owner used. He obviously didn't do a very good job with this thing based on the flue pipe mess I found. Both slots are the same. They are both Fasco units rated at 75 cfm. I guess I'll need to come up with a plate for the combustion blower and maybe look at a higher cfm fan for the distribution blower.

Is the 3M fire block a good product for sealing the seams? Do I just use it around the outside of the joints or pull them apart and put it between the joints?

Just use a piece of duct tape or a flat fridge magnet as a restrictor plate. Cover about 1/2 the intake to begin with. I think I made one up out of the bottom of a cat food can on one of the stoves I re-habbed.

Good point by cn760 about the wet coal, the manual says on EVERY page DO NOT USE WET COAL.

I will check later to see what cfm my distribution fan is rated if nobody else provides that info.

Yes that flue pipe was awful. Since this is a new install for you, you should plan to check the flue pipe after about a ton of coal has burned to see how blocked up it is. The fly ash will accumulate int eh horizontal run, not so much in the verticals as you witnessed by how clean the chimney was. You can then make a judgement on the cleaning interval you need by how much is there after a ton.

Fire block should be good. I just put a bead at the seam and smoothed it out a little on mine. you don't need to take the pipe apart.

Get a flap on draft blower, if your handy fab your own with aluminum coil stock or thin sheet metal. If you are using bagged coal try and dry the coal before placing in the hopper. Open bags and dump contents in a plastic pail several days before you plan on using it. I use to use about 5 pails to dry bagged coal.

I'm heading off to work right now but first thing tomorrow I'll fab up a plate for that blower. My coal is completely dry. It's been sitting in a bin in my garage since last season. When I pour it into a bucket it makes dust so I can't see that being the issue.

I'm not seeing a lid on the hopper in any of the pictures. Is there one? I believe it supposed be on there when the stove is in operation.

Heavy foil tape works well at pipe joints.

SWPaDon wrote:I'm not seeing a lid on the hopper in any of the pictures. Is there one? I believe it supposed be on there when the stove is in operation.

I do have a lid for the hopper although I haven't been using it. I'll start putting it on.