Coal Not Burning Totally to Ash

blrman07 wrote:Yep difference between a stoker going to a chimney and a stoker going to a direct vent fan. Direct vent has to be set properly for it to pull the air and gasses from the stove and push them outside. The direct vent fan has to be pulling more than the combustion fan is pushing in so the firebox will be in a negative pressure. If they are not balanced out then the combustion fan will put more air in than the direct vent is pulling out. Then the gasses stop flowing and when that happens the fire will go out.

OK, so I do that by pulling out the rod on the vent motor? I'm guessing just a little at a time? The guy that got me going on this told me not to mess with the rod on the vent motor, but it sounds like I have to. The rod is just about all the way in now. He told me pulling the rod out pulls less draft. Is that correct? Is that what I need to do?

I am betting that when it gets cooler outside you will have less of a problem and will likely get a decent burn. Can you post a picture of your stove showing the direct vent?

Does it sit up on top of the stove at the outlet or at the bottom rear of the stove at the outlet? Once we see exactly what you have then we can try to punch a manual or instructions to you

You will need a eventually need a manomter to ensure that the direct vent is set properly . It's not something you want to do trial and error for long run but in a pinch you can "ballpark it".

Be sure and notify the Director of Domestic Tranquility in your home that you are working on the problem and making progress!!!

Oh, and also should this help my original problem of the coal not burning all the way?

Here are hopefully a few decent pics of the vent kit. Any help? Its at the bottom rear of the stove. And "Director of Domestic Tranquility", I like that. The problem is I've been talking this coal burning up for a while. And now when we need it, its not working out. I can only use the "I'm dialing it in" for so long.

what kind of coal you burning??

mattcoalburner wrote:what kind of coal you burning??

Cornwall coal (rice) Buck Digs Premium Grade

yea cornwall is decent coal

Glad to hear that.

the coop wrote: and also should this help my original problem of the coal not burning all the way?

Well...just to add confusion.... no one has mentioned that the Reading Lehigh uses the ol' "Tri-burner" system. It has one motor that moves the coal down the burn plate and at the same time is the fan that blows air on the coal so it will burn. When the coal stops moving, the fan stops with it. I believe THIS is why some coal is unburned and also perhaps why the fire goes out during low demand. Once it gets colder outside and you have more demand, both problems should go away. That being said...two more things... one: You should get the manometer and KNOW your draft. It's important. Two: There is a complete cure. It involves a retrofit (a handy guy type of thing). You buy a tiny blower motor, hole saw a 1 1/2" hole and add the new blower. You make it so it runs all the time. Now, all coal burns, you get pure ash. Almost every stove works this way except the tri-burner. If you search this Forum for "Tri-burner" I'm sure you'll find details.

Oh! And.... make SURE you have a CO detector! If you do not, stop burning now and get one before you burn again.

There is a learning curve, but in a while you and more importantly the DODT will love it.

Freddy, I do have CO detectors. This is the first I'm hearing the tri-burner mentioned.I will search that. Also just out of curiousity, where would the new blower motor go if I were to put one on? If it were running all the time, it wouldn't make it burn to hot?

I would like to take a second and thank everyone for their input. It gives me hope. I really appreciate it.

Before you bust out the holesaw, you need to get the draft properly adjusted. Once that is done, you might find that a small increase in the idle time is all that is required to keep the fire burning.

Am I correct in assuming that pulling that rod out on the direct vent will pull less draft? Because its almost all the way in now. So pulling it out would make it worst?

That rod controls a flapper that is next to a cutout inside the unit. One direction increases the amount of room air that is pulled into the vent piping, the other direction decreases the amount of room air pulled into the vent piping. If less room air is pulled into the vent piping that means more is pulled through the stove via the grates. This is what will increase the draft inside your stove which is what you want. The plate over the cutout is held in place with four screws. Can you find that plate and remove it then move the rod and you will see which way closes it off and which way opens it up?

Only problem is I don't have one of those type of direct vents. I don't remember which direction will increase draft through the stove. Maybe we can get you ballparked until you get a manometer to set the draft through the stove properly.

Someone will chime in pretty quickly here who has the direct vent with the t handle. I will continue to research and let you know what I find.

I found a plate that has 2 screws in it. It looks like it slides out. I can only get at 1 screw with the vent in place. I would have to take the vent off and dis-connect the pipes to get to the other screw. This is the only plate that I can see. If the guy that helped me with this is correct, all the way in is more draft. Thats where it is now. So I need more than that?

I wouldn't recommend trying to achieve 0 unburned coal. In the stoker units I'm familiar with, that's a sign that you are using too much combustion air. If your unit holds the fire, doesn't push live coals off the burn grate and produces an appropriate ash band, you're doing ok. Most stokers tend to produce more unburned coal under light or intermittent load, but most of your coal gets used when the unit is working harder.

Mike