When outdoor temperatures are low, your furnace provides more than comfort—it’s also important for your family’s safety. This being the case, many people wonder how long their furnace will last, especially if they have an older model.
The standard for measuring furnace life is the heat exchanger. Not only is this the most vital part of the system, it’s the one piece that can’t be repaired or replaced. Once it fails or cracks, it’s time to buy a new furnace. Because of this, furnace life varies heavily based on the quality and type of the heat exchanger.
Surprisingly, older furnaces often live longer than their modern counterparts. In the past, heat exchangers were often built with heavy metals, such as cast iron. These exchangers can last as long as 30 or 40 years, much longer than the steel exchangers most manufacturers build today. Modern stainless or aluminized steel heat exchangers typically have a life span of 15 to 25 years.
Furnace Maintenance Tasks
So why do forced air furnace heat exchangers usually survive an average of 15 years? The answer is simple: your furnace’s life span depends heavily on how you treat it. Follow these simple guidelines to make sure your furnace lasts as long as possible:
- Change the air filter regularly – If your furnace’s filter is dirty, it restricts the amount of air the system gets. This can cause it to overheat, further reducing the life span of its heat exchanger. Most furnaces need the air filter changed every 30 to 60 days, but make sure to follow your manufacturer’s guidelines. This should allow the system to run at top efficiency and stay within manufacturer’s specifications.
- Reduce moisture levels – You’re not the only one bothered by the area’s oppressive humidity. Your furnace hates it too. High moisture levels can cause your heat exchanger to rust, greatly reducing its life span. Winters here are usually more humid than summers, making this an even bigger problem. If you’re finding that moisture builds up on your heat exchanger, consider getting a dehumidifier for the house.
- Clean the A/C coil – If your air conditioner and its coil is on top of your furnace, making sure that it’s clean will not only increase its life span, but your furnace life as well. Cleaning the coil will help keep the drain from plugging and leaking condensation on your furnace. Not only can this lead to rust and corrosion on the heat exchanger, it can also damage your furnace’s electrical parts.
- Get proper maintenance – Benjamin Franklin once said that “an ounce of prevention is worth a pound of cure.” While this saying has many applications, it’s especially true of furnaces and other HVAC systems. If your furnace isn’t running within the manufacturer’s specifications, it can drastically reduce furnace life, as well as lead to costly repairs.
More on Annual Maintenance
Schedule an annual maintenance appointment with an HVAC specialist. They’ll be able to check your heat exchanger for integrity, test for carbon monoxide leaks, make any necessary settings adjustments, examine your venting system and chimney, seal the duct connections, clean and lubricate the blower, and remove any corrosion, soot and dirt from the furnace itself.
Regular maintenance isn’t just part of extending furnace life. It’s also part of keeping your home safe. A faulty or leaky heat exchanger can be difficult to notice and very dangerous, considering it releases combustible gases into your home’s air. Other problems, like dirty ducts, can cause or aggravate health issues. Your appointment will also increase your furnace’s efficiency, reduce utility bills and increase its performance, leading to more comfort.
Sometimes Replacement May Be Necessary
It’s important to note that while furnace life is measured around how long the heat exchanger lasts, there may be situations in which you should replace your furnace even if the exchanger is in perfect shape. Even a perfectly maintained heat exchanger will eventually fail, due to the constant cooling and heating of the metal. No one can guarantee how long your furnace will last, but by taking these measures, you can greatly impact its expected life span.
If you have any questions about your heating system or what you can do to increase furnace life, contact Griffith Energy Services, Inc. We’re available 24/7 and have been serving the Mid-Atlantic region for over a century.
Written by Kevin Spain