My home is over 106yrs. old. We have central heat in the main level which is run off of propane. We do not have any source of heat for the three bedrooms upstairs, except for space heaters which seem to blow fuses when two are running up there. We would like to find a way to not only get some heat upstairs but also supplement our propane use on the main floor. What is our best and definitly most economical options? We also do not have ANY insallation in the attic which I know We must consider.Please help!