New to the forum with some safety questions about coal.

ecco123 wrote:I always thought the bigger the chimney the better!

It's the taller the chimney the better, at least within reason. A large chimney only has greater capacity but needs that much more heat to draft well. That's why fireplace chimneys are so big. They need the capacity to handle a big fire and the big fire makes enough heat to make it draft. A chimney in the interior of the house will be warmer and draw better regardless of size. In the colonial houses of America the chimneys were always in the center of the house.

That you get smoke loading wood which has a hotter stack temperature and so better draft is a sure sign to at least suspect that the draft is not enough. Remember draft is created by hot air rising. If the chimney is cooling it too much it will not rise.

Any heating man should be able to measure the draft for you at the boiler breech and over the fire with a small hole in the loading door, or you can buy a manometer yourself for about $25 for the Dwyer Mark2 instrument. Then you will have definite figures to go by to make a decision rather than guessing.

There are simple things you can try to improve draft but lets get some figures first before making decisions. Measure the draft with the boiler running and with a simple magnetic thermometer the temperature of the smoke pipe about a foot after the boiler. Do this under typical running conditions.

I had a yellow flame coal fired boiler that burned rice coal but the concept should be the same. I noticed that you had both the upper and the lower door open at the same time. If I forgot to completely close the lower door and opened the upper door, fumes would roll out the top door. That happened every time I had both open at the same time for whatever the reason. The draft on my chimney wasn't the best and it would go to minimum if I had an ash buildup in the smoke pipe or where it entered the chimney. With both doors open the draft took the past of least resistance which was in the bottom door and then right out the top door instead of going up the chimney. I fixed that by making double and triple sure that I only had one door open at a time and there was no ash buildup anywhere in the smoke pipe or at the entrance to the chimney.

Try only having one door open at a time and see if that lessens the fumes problem.

I went back and watched that video again very closely this time. The smoke pipe comes out the rear of the boiler and goes straight into the chimney. There is a T and it appears that the drop leg part has a cloth tied around it at the base. If this is the case, your loosing draft right there. I suspect that if you put a smoke source like incense or a cigarette near that T I'm betting that you will see the smoke being drawn into the drop leg on that T if it only has a cloth tied over the opening. Worth a check and it can be completed without a big hassle. If it does draw in smoke put a cap on it.

Rev. Larry

i have to agree with rev. larry check out that rag on the T do what the rev says

David,

Bienvenido al NEPA! Aqui hay mucha gente que entienden el carbon. Creo que el carbon que tienes es entre anthracite y bituminous. Pude que nececitas abrir la valvula en la puerta para mejor combustion de tu carbon. Es una lastima que el orno no tiene shaker grates. El diametro del chiminea is importante - mejor el diametro correcto que grande... eso es un tema complicado... Parece que el problema is la chiminea... Vives circa Zarragoza?

Welcome NEPA! There are a lot of folk here that understand coal burning. I believe the coal you have is a grade between anthracite and bituminous. It may be necessary to open the vent on the door to get better combustion of your coal. It's a shame that the boiler doesn't have shaker grates. The diameter of the chimney is important - better the correct size than too large a diameter... this is a complicated subject... It does appear that your problem is the chimney... Do you live near Zarragoza?

dj