Many furnaces are also equipped with glass doors that are especially necessary when the fireplace is warming up and can not deal with smoke and thus lets the bitter smell in the room. The glass cover helps to prevent it. The doors can be swinging or lifting. By the way, furnaces with a fireproof door are safer than open grates, and allow you to manage the flow of warm air much better and easier. The only drawback is that sometimes the heat-proof glass may be covered with soot.
Taking measurements of your fireplace is one task you should perform before researching the costs and types of fireplace blowers available, if you are planning to affix it to your fireplace. If you are uncertain of which type or style to purchase, then determine what your specific needs are for the blower. Once you have an idea of what you want to use it for, then you should be able to ask the right questions of the retailer or store proprietor.