ive just built a coal fire in my lounge but the first time i lit it i got smoke coming into the back bedroom from the chimney brest but nothing in the front bedroom got a builder round told me to reopen the vents in bothrooms ive done this and cured the smoke problem in the back bedroom but now ive got smoke in front bedroom but if i open the window it stops its as if the smoke goes out one chimmney and down the other can i cap them off PLEASE HELP A PI---D OFF BLOKE!!!