HS Tarm 500 burning coal w/only 140* output (HELP)

Hi, I have been trying to burn coal in my HSTarm 500 for many years. I get a full bed of coal looks great but it is producing only 140* and the oil burner keeps coming on to get the water up to temp. I m so frustrated I could scream, but no one would hear me as I m always in the basement trying something new. Should the round damper on side be open or closed? Should the door on the bottom front be open or closed? If open how far? Should the round door on the front be open or closed? Right now I have the side (round) door slightly open. The bottom draft door 1/2 open and the round draft door on front closed? Also can u put new gaskets on the doors w the fire burning? I m single and have no one to bounce things off of.

Welcome to the forum! You should be able to get some good information, lots of great people here. Hopefully someone with the same model will chime in to trouble shoot. Could just be a matter of technique. Coal has some learning curve and the same rules don't apply if you are used to burning wood. A couple key points, coal needs air coming up thru the grates to get it to produce good heat. Try letting in combustion air from underneath the grates, cut back any air coming in over the fire to a minimum. Hopefully the grate system doesn't have any way for combustion air to get around the grates instead of going up thru them.

Draft is also very important. You may need a manometer to check it. Most coal burners here have one permanently installed to monitor draft pressure continuously. Manometers are cheap and simple to install

ALSO, you must be able to shake the grates to clear ash from the coal bed. Don't be afraid to shake them vigorously, short choppy strokes don't reef on anything. If a piece of coal should lodge in the grates, let it burn or use somekind of poking tool to dislodge it from underneath.

Thank you for the reply. I will look into getting a Manometer. Although, I don t really understand the concept. Seems when I open up the bottom door and side air the coal gets very red but the temp doesn't t go up very much. I have the barometer covered. Will take any advice I can get, need to get it working efficiently.

Do you have the manual for that boiler? If not, you can get one here: http://www.woodboilers.com/images/stori ... manual.pdf

Take the time to read the entire manual, especially the coal-burning section.

I believe that model HSTarm is supposed to have a baffle inserted when burning coal. It allows you to run a deeper coal bed without blocking the flue. The manual says the most common reason for inadequate output in that boiler is not adding enough coal.

Today was reading and it suggested opening bottom 2 openings (more) as coal supposedly drafts from the bottom. Also shook it down w quick shakes leaving 2" on bottom put on 3 small shovels. I Checked it 7hrs later temp still only 140* . By the way had a nice bed of coals. Can you hear me I m screaming. Haha, not really but so sad.

SMcCarthy wrote:Thank you for the reply. I will look into getting a Manometer. Although, I don t really understand the concept. Seems when I open up the bottom door and side air the coal gets very red but the temp doesn't t go up very much. I have the barometer covered. Will take any advice I can get, need to get it working efficiently.

Is the barometer covered temporarily? Or covered as in burning wood? I don't know what your draft should be, but a covered baro. will send alot of heat towards your neighbors!

Maybe something is not right with the Samson Valve.

Try blocking it open for a while...Be sure to stay there for the entire duration it is blocked. So you can unblock should it take off roaring.

Do you have the baffle plate installed for coal? Without it you're in wood burning mode.

Coal loaded all the way to top of bricks and mounded higher in the middle?
How thin or deep you make the coal bed is not an judgement option...it is required to be deep to work properly.

SMcCarthy wrote:Also shook it down w quick shakes leaving 2" on bottom put on 3 small shovels. I Checked it 7hrs later temp still only 140* . By the way had a nice bed of coals.

Fill the boiler up with as much coal you can before coal is spilling out the load door. You need a DEEP coal bed. You might not have enough of a hot coal bed to heat the boiler water.

I would check the baffle on the oil burner side. I understand that Tarms will burn through it to the other side, could cause a problem.

Hi thank you for the responses. I have only the two up right pieces don't remember ever having a bottom piece. In the past I had them in and the fire went low and they fell down and a piece burned out of one of the up rights can I still use them? Do I have to have the bottom piece to make the up rights work? I will try and rake fire up from the back and see if that helps. How do I check to see if that side thing has burned through. Btw that side vent comes off it is not hooked on, is this bad?