In the winter months, your furnace is the most important factor in keeping your home comfortable. It is important to know the signs that your furnace may need a tune-up to avoid a breakdown that leaves you in the cold. Here are three warning signs that could indicate that your furnace is in need of repair.

Yellow or Flickering Burner Flame

When your furnace burner is getting the right mix of gases, it will produce a steady blue flame at all times. If your burner flame is yellow or flickering, it's a sign that something is off with the balance of gases in your furnace. There is also a risk that your furnace could be emitting potentially dangerous levels of carbon monoxide. If your furnace flame is yellow and your family is experiencing symptoms such as frequent headaches, nausea, disorientation, or flu-like symptoms, you should turn off the furnace, exit your home, and contact a technician immediately.

Noisy Furnace Operation

There's no such thing as a completely silent furnace, but excessive noise while the furnace is running could be a sign of a problem. The sounds a faulty furnace makes will depend on the component(s) that are failing.

One common cause of a metal-on-metal scraping sound is a blower wheel that is scraping against the blower casing. If you hear squealing or whining noises, a likely cause is a slipping belt that may be easily and inexpensively replaced. In some cases, squealing noises may mean that bearings in the blower need to be oiled.

Increasing Heating Bill

If you are not changing your furnace usage patterns, your heating bill should not vary too much from month to month. A sudden spike in your bill could be a sign of a malfunction that has significantly decreased the efficiency of your furnace.

Long-term efficiency lost can be harder to notice, as it leads to a slow upward creep in your bill that can take place over a number of years. Gradual efficiency loss is an unavoidable consequence of a furnace that is nearing the end of its lifespan. The best way to determine if it is time to replace your furnace is to hire a technician to analyze the annual fuel utilization efficiency of your furnace.

Keep these signs of a failing furnace in mind and inspect your furnace at least once a month so you can get minor problems repaired before they lead to a breakdown and more serious damage to your furnace.