When you fire up your furnace for the season’s first use, you may experience a burnt dust smell. This odor is harmless and should not last more than a few hours. To get rid of the smell quickly, try a filter change.
An electrical odor is more of a concern. Causes may include an overheated motor, broken fan motor, clogged filter, fried circuit or wiring problem. Turn off the furnace immediately and contact a professional. A burnt plastic smell may come from objects lodged in the furnace. Toys and other plastic objects give off fumes when heated, and this off-gassing may be dangerous to your health. Schedule service if the smell persists.