You should only hire licensed contractors to install an oil furnace in your home. As with any combustion-based furnace, there is a potential for lethal carbon monoxide buildup with these furnaces. If you hire an unlicensed contractor, then you don't know much about his or her qualifications. Licensing ensures that the contractor understands all the dangers of this type of work. It also generally requires the contractor to verify his or her education and employment on a legally-binding government document. Never hire an unlicensed contractor to do this type of work for you.

Find references for any contractor you consider hiring. Local references are best, but you could also settle for online reviews of the contractor's services. These reviews will tell you a lot about how the contractor operates while on the job.

You should write out a contract between you and the contractor before he or she gets started on your furnace. The contract should cover every single aspect of the project including the scope of the work and any payment terms. This document will go a long way toward making the entire job move along very smoothly.