I have an old fisher heater that we used when i was a kid but has been in storage for years now. I live in a 16x80 trailer with electric heat strip heat that makes the power company love me, that I cant afford this year. What I want to do if it will work is to build a small block building, i have tons of block so no cost is what i am after, then making a sheet metal chamber around the heater about 24" on each side and top larger than the heater sealing it against the heater so smoke want get in. Then installing duct from the top of the box running it under my trailer and connect it to my existing duct. On the bottom of the heat chamber I was going to cut in a squirrell cage fan pulling air from outside pushing into the chamber and run it on a thermostat. Will this work and do i need to put a thermo controlled damper on either end or both ends of the duct? Any ideas will be greatly appreciated. Thanks.