titleist1 wrote:What is the construction & size of the chimney?
Not sure if I describe it properly but I will try. The liners are tera-cotta? and the outside is cinder block construction. I have three flues in one chimney. The center flue is a large 12x18 that comes down to a 4' opening for a large fireplace. I installed my Harmon here. The flue for the oil burner is directly next to this flue at the top of the chimney but then takes a turn to get around the wider opening at the top of the opening of my fireplace (firebox?)then continues next to the fireplace down to the basement. All of this is encased in cinder block and red brick in the living room and above the roof. The other flue goes to a thimble opening on the other side of my fireplace that could only be used for a small stove, not really applicable here.
There are I guess two issues with the oil flue. The chimney guy claims cracking at the top and he says also down below. I have a cap on the center flue which he suspects has been directing extra water down the other flues. (He offerred a multi-flue cap to fix this and a few hundred bucks to replace the top masonry liner pieces...perhaps this addresses his concern of code issues with the cracking visible from the top...I need to clarify with him)
The second issue which concerns me a little (not sure if it should..) is that last year when he cleaned the oil flue (first time we have ever had this done) he jabbed his brush through the wall of the liner where it bends around the fireplace flue. He claims it so brittle that it went right through. Now I have a hole between the two flues above the firebox that he said he could not reach to repair without dismantling the fireplace. He claims this is ok for oil but would require a liner for anything else..and he can't bend a liner around the larger fireplace flue so he would have to do major surgery to put it in, suggesting it go right through the fireplace and a new hole in the floor making the fireplace essentially unusable ever in the future. The small insert liner (10') that I installed for the Harmon Mark II extends beyond this hole so I think the coal stove is venting fine through the larger flue. He said the smaller flue for the oil furnace would draft better than the larger one so the oil furnace should draft properly through it's own flue rather than seeping through the hole into the larger flue.
I hope I described it properly...I know a picture would help but the fireplace plate is back on around the stove vent so the hole is not visible now without taking the whole thing apart.