If you decide to PLEASE use approved chimney pipe. In our mobile home we installed a wonderful little Dutchwest stove (mobile home approved) and the proper flue/chimney pipe. There are several potential problems with not installing an approved stove, of course the first one is a fire that can consume your whole home in about four (yes, that's right!) four minutes. Be sure you don't go to bed or leave home with fire in your unapproved stove. Somethings are just too scary to think about.