How Long Does A Furnace Last?

senior couple with heating bill turning down thermostat

Some of the most common questions we get at this time of year are how long do furnaces last and how to know when it’s the right time to replace and install a new furnace. The honest answer is that the right time will be slightly different for everyone, depending on:

  • Risk tolerance: are you willing to risk a sudden breakdown?
  • Energy costs: how much of a burden are your monthly bills?
  • Your budget. If you’re looking for a more affordable option, we provide Furnace Rentals in the Greater Toronto Area.
  • Comfort situation: do you have warm or cold areas in your home, and do they bother you?

But there are some warning signs you should pay attention to in order to save the most money long term and avoid sudden breakdowns.

Average Lifespan Of Furnace

In general, you can expect a well-installed, regularly maintained furnace to last about 15 years. Our climate is cold here in Toronto, and furnaces have to work hard for about 8 months every year. Make sure you know how to tell the age of your furnace before taking action.

There’s an advantage to shopping for a new furnace before it breaks down completely. It gives you time to decide on the right model and even take advantage of seasonal discounts or rebates. If it’s February and your gas furnace dies and you’re stuck, you may not get the best possible deal.

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Older natural gas furnaces, however, are not nearly as energy efficient as newer models, which brings us to the furnace efficiency question.

This chart shows you cost of repairs, age of furnace, and how these affect whether you should repair your existing furnace or buy a new one.
This chart shows you cost of repairs, age of furnace, and how these affect whether you should repair your existing furnace or buy a new furnace. If your furnace has a red tag, get it replaced immediately.

How To Tell It’s Time To Replace Your Furnace

1. You Need to Reduce Your Energy Bills

Technology has come a long way in the last 10 – 15 years, and huge improvements have been made in how much energy they use. In the 1990s, for example, furnaces averaged about 80% efficiency. Today, the legal minimum in Canada is 90%, and it’s common to find furnace models with a much higher rating than that. The EnergyStar program recommends replacing any furnace that is 15 years old for efficiency reasons.

In your furnace manual, there will be a number called an AFUE (annual fuel use efficiency) rating given as a percent. Compare that number to the efficiency of a new furnace, and you’ll get the difference in efficiency. When you apply that to your winter heating bills, you can see how much you would save.

Also, keep an eye out for sudden increase in fuel usage on your gas bill. If the price per unit has remained the same and so have your usage patterns, your natural gas furnace may not be working as efficiently as it used to.

should I repair or replace my furnace chart
This chart shows you cost of repairs, age of furnace, and how these affect whether you should repair your existing furnace or buy a new one.

2. Repair Bills are Adding Up

Just like your car, your furnace depreciates. Once your repair bills reach $600, it’s time to compare repair costs to the age of your furnace and decide if it’s worth it to keep making repairs.

For a newer, high efficiency furnace, a single $350 repair bill worth it. A 10-year old furnace may not be worth such a large investment. As a general rule of thumb, once repair costs reach half the cost of a new furnace, replacing definitely makes more sense.

3. Your Furnace is Making More Noise

As furnaces get older, they can start to make noises like pops and bangs. Aside from the annoyance, this could be a sign that parts are getting ready to fail. It can also mean that your ductwork is not sized correctly for your home.

If noise level is a concern for you, ask your technician about sound levels for any new furnaces you may be considering.

4. You See Signs of Rust, Cracks or Excessive Soot

These signs definitely mean that your furnace needs to be inspected with our furnace inspection checklist, at the very least. The worst case scenario is that your furnace is a safety hazard.

Because your furnace burns fuel, it has certain natural byproducts that can be deadly, mainly carbon monoxide. Usually, these are vented safely up the vent, but if your furnace is older, there may be cracks or other flaws that mean gas is leaking into your home.

5. Your Furnace Cycling Pattern Changes

If your furnace is turning on and off more frequently, or stays on longer than it normally would to heat your home, it may be a sign that some parts are failing and others are working harder to make up for it.

6. Your Furnace Doesn’t Keep the Whole House Comfortable

Most homes have natural warm and cool spots, depending on where they are on the ground floor or another story, the number and size of windows, insulation quality, and even ceiling height.

If this bothers you, newer furnaces are much better at keeping a regular temperature, even if your home isn’t divided into multiple temperature zones.

How to Extend Your Furnace Life Expectancy

1. Install a Programmable Thermostat

Overworking your furnace is a great way to send your furnace to heaven early. Although you’re currently toasty warm, you’re diminishing your furnace’s longevity. Without implementing balance with your furnace usage, you’ll need to start booking the funeral.

But, we’re human. Sometimes we forget to turn it down or off. So, how do you create a balance with your furnace’s usage without human error? Introducing smart and programmable thermostats.

Nest Learning Thermostat

Installing a programmable thermostat controls the usage of your heating system. Basically, it allows you to set a predefined schedule that adjusts the temperature of your home based on time of day and season, turning the heat down at night and during the day when no one is around.

Smart thermostats add an additional level of control by reacting to movement (are people home or not), creating schedules on the fly, smart control via phone apps and additional tracking to allow you much better control of your system – from anywhere in the world. Not only are they useful for furnace longevity but these new thermostats will also save you money on energy costs.

2. Replace Air Filter

If your air filter looks like an old, dusty accordion, it’s past time to replace the filter. Often neglected, your air filter can cause your furnace to blow cold air and drain the life out of your furnace if not replaced or cleaned. The air filter function is to clean the air and protect your system from allowing dirt and debris to enter the furnace.

GeneralAire AC22 And AC24 Cleaners

When dirt begins to cover the filter, your furnace must work much harder to move air. Because dirt and dust are covering the filter, the furnace fan will need to work hard to overcome the additional resistance. Also, since less air is moving through the system, your furnace will need to run longer in order to raise the temperature. Our Dr HVAC suggestion is to clean and check on your air filter regularly. By doing so, you’re allowing your furnace to emit warm air normally without any obstructions.

3. Prevent Air Leaks

Air leaks rob you of the warm air your furnace works so hard to produce. Not only do air leaks drain your home of that warm air but it also pushes your furnace to work harder and longer, resulting in a reduction of its lifespan. Your front door, windows, walls, bathroom and kitchen vents, basement intrusions and any small gaps and spaces can allow air to infiltrate.

Preventing drafts and eliminating air leaks to ensure your home is properly sealed and insulated is one of the best things you can do to improve the comfort of your home as well as the life of your furnace.

A useful trick to determine if your door or window is causing an air leak is by lighting an incense stick and placing it in front of your inspecting area. If the smoke rises up, there’s no leak. If the smoke moves in a different direction, you have a leak. Most big box DIY stores have a whole section on weather stripping and caulking to help fill these gaps and stop leaks.

4. Perform Regular Maintenance

To avoid the nightmare of getting your furnace repaired, we recommend having your furnace cleaned and maintained at regular intervals. When you get your furnace tuned up, an expert HVAC technician will run through an extensive checklist of items to ensure you’re eliminating future issues that could occur on the coldest Brampton winters.

Why not schedule your maintenance with us, Dr HVAC. We understand the hustle and bustle of everyday life and how a broken furnace needing repairs can throw a wrench into your schedule. By performing maintenance with us, you can expect an immediate response and honest, hard work. Schedule your maintenance and trust the doctor.

It All Adds Up – Replace Your Furnace!

As you can tell, you need to weigh multiple factors together in order to make your decision.

If you need more information about what the options are for a new furnace, don’t hesitate to ask us for a free quote. You’ll love our no-pressure process, in which you receive everything in writing up front.

Want to learn more about making your furnace last longer? Here are some simple maintenance tasks any homeowner can do.

Check Out Our Maintenance Tips


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