Hello everyone. I need advice badly.
To start, I have a brick house (which is around 1100 square feet) with a masonry chimney. The flue blocks are surrounded with cmu up to roof and then transitions to brick on the outside. The top of chimney is about 2'-4" above the ridge, but total height of chimney is around 9'-0" from where wood stove pipe pokes through wall into chimney to top. The flue is 5 3/4" x 6", and our stove is 6" dia.
I had a company come out and clean my chimney. The guy told me that there were cracks in the flue, and that there was portions that had glazed creosote on it. He said that the cracks were partly (if not mostly) to blame for the poor draft. I asked how big the cracks were and he told me that they weren't that big but you don't need much to cause a problem. He said he wouldn't even start a fire if it was his family. He told us it would be around $2400 to remove the flue and put an insert in.
Questions:
1. If the cracks aren't all the way through the cmu, how can it be causing a problem?
2. I've read where if the chimney is shorter than 12'-0" than there's inherently a draft problem, so if he replaces with the same height are we still going to have a blow back issue?
I know there are questions I still need to ask, I just don't know what they are.
Please help. I wasn't prepared for this and now it's mid Oct. My fault for letting the chimney cleaning slide down the large priority list.