How Much Does it Cost to Replace a Furnace Heat Exchanger? A Portland Tech Answers

If you’ve been told that you need to replace your furnace heat exchanger, you may be wondering how much it will cost.

The cost to replace a heat exchanger in Portland ranges from $1,500 to $3,500.

We know. That’s expensive! The reason it costs so much to replace a heat exchanger is because the heat exchanger is an expensive part that can take eight hours or more to replace.

In this blog, we discuss:

  • What a heat exchanger is (and why they sometimes need to be replaced)
  • Whether you really need to replace your heat exchanger
  • When it’s more cost effective to replace the furnace
  • What factors contribute to the cost of replacement

Rather talk to an HVAC professional? Contact Four Seasons to talk to a trustworthy, NATE-certified technician.

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What is a heat exchanger (and why do they sometimes need to be replaced)?

The heat exchanger is the part of your furnace that heats the air.

Your furnace works by heating up a series of coiled tubes encased inside metal walls. This metal contraption is the heat exchanger. The blower pulls cold air from your home into your furnace and that air warms as it passes over the hot walls of the heat exchanger. The blower then pushes the warm air back into your home.

Over time, heat weakens joints in the walls of the heat exchanger. A heat exchanger that overheats is especially vulnerable to forming cracks. Overheating is most commonly caused by a dirty air filter which restricts the flow of cool air over the heat exchanger.

Exhaust gases, including carbon monoxide, build up inside a heat exchanger and are normally vented outside your home. When a heat exchanger cracks, carbon monoxide leaks outside the heat exchanger and into your home, possibly putting your household at risk of health problems.

Do you really need to replace your heat exchanger?

If your heat exchanger is cracked, you must replace it because a hole or crack in the heat exchanger can release dangerous carbon monoxide gas into your home.

So, how do you know if your heat exchanger needs to be replaced? You only need to replace a heat exchanger if it actually has big enough cracks to warrant a health hazard.

Signs that your heat exchanger has dangerously-sized cracks include:

  • A visible hole or crack. An HVAC technician who recommends that you replace your heat exchanger should be able to show you the hole or crack.
  • Soot on the inside of your furnace. Soot buildup on the inside of your furnace indicates that something isn’t working correctly, which could be your heat exchanger.
  • An eye-watering chemical odor. As well as odorless carbon monoxide gas, other poisonous fumes leaking out of a cracked heat exchanger have a strong, eye-watering chemical odor and can cause headaches, nausea and other physical ailments among the occupants of your home.
  • Carbon monoxide poisoning. Carbon monoxide is particularly dangerous because it is odorless and invisible. Symptoms that carbon monoxide is leaking into your home from a cracked heat exchanger include dizziness, nausea, and lethargy.
  • An alert from your carbon monoxide alarm. An alarm from your carbon monoxide detector can indicate carbon monoxide gas escaping from a damaged heat exchanger.

When is it more cost-effective to replace the furnace?

It may be more cost effective to replace your furnace if it’s over 10 years old or if it isn’t meeting the heating needs of your home.

A heat exchanger tends to develop cracks when a furnace is near the end of its lifespan (10+ years). If your furnace is nearing the end of its lifespan, your heat exchanger may be the first of many parts to fail.

Another reason to possibly replace your furnace is if it isn't meeting the heating needs of your home anymore. An inefficient furnace will increase your utility bill.

In either case, it may be more cost effective to replace your furnace than to continue shelling out money to maintain and repair an old or inefficient furnace.

If, however, your furnace is fairly new and/or the heat exchanger is covered by the parts warranty, it’s more cost effective to repair the furnace by replacing just the heat exchanger.

Now let’s discuss the parts warranty and other factors that impact the cost of replacing a heat exchanger.

What factors contribute to the cost of heat exchanger replacement?

The amount you’ll pay to replace your heat exchanger is affected by:

  • The type of furnace you have
  • Whether the heat exchanger is covered by a warranty
  • Contractor experience

Factor #1: Type of furnace

The cost to replace your heat exchanger is affected by:

  • The age of your furnace. The more difficult it is to replace parts for an older furnace, the more it will cost.
  • The size of your furnace. The bigger your furnace, the more you’ll pay to replace the heat exchanger.
  • Your furnace type or manufacturer. The cost of a heat exchanger varies between manufacturers. Replacing a heat exchanger or secondary heat exchanger will be more costly for a high-efficiency furnace than a standard furnace.

Factor #2: Warranty coverage

You can save $500 to $1000 on a heat exchanger replacement if your furnace is covered by a warranty.

Furnaces come with two warranties:

  • The parts warranty (also called the manufacturer’s warranty). The parts warranty provided by the furnace manufacturer (e.g. Goodman or Daikin) covers the cost of defective parts but doesn’t cover labor. A heat exchanger is generally covered for 20 years by parts warranties.

However, it’s easy to accidentally void the manufacturer’s warranty. You might accidentally void the warranty if:

  • Your furnace hasn’t been maintained annually by a licensed HVAC technician
  • Your furnace has been repaired with an off-brand part
  • Your furnace has been repaired by an unlicensed technician

To determine whether or not your heat exchanger is covered by warranty, look up your furnace’s serial number on the manufacturer’s website.

  • The labor warranty. The HVAC contractor that installed your furnace can provide a labor warranty that covers your furnace anywhere from 60 days to 2 years after the installation, depending on the contractor. A labor warranty covers the cost of labor to correct problems due to a poor installation but typically doesn’t cover the cost of parts.

If your furnace is fairly new, contact the installer to determine if the furnace is still covered by a labor warranty.

Factor #3: Contractor experience

Contractor experience will determine how much you’ll pay for labor to replace your heat exchanger.

Because labor is a large factor in how much you’ll pay for a heat exchanger replacement, you may be tempted to hire a cheaper HVAC technician. However, cheaper almost always means inexperienced, which can cost you more in repairs down the line. To ensure quality service, you should hire a reputable HVAC technician with 10+ years of experience.

Make sure the HVAC technician you hire is:

  • Licensed, bonded, and insured
  • NATE-certified in the state of Oregon
  • Experienced with 10 or more years of HVAC service
  • Highly rated on Google reviews

Ready to hire an HVAC professional to inspect your furnace?

If you suspect that your heat exchanger needs to be replaced, turn off your furnace and contact a licensed HVAC technician like Four Seasons for a furnace repair.

Our NATE-certified HVAC professionals will thoroughly inspect your furnace to determine if the heat exchanger needs to be replaced.

When you choose Four Seasons, you will always get an honest recommendation, a fair estimate and exceptional service during every step of your heat exchanger replacement.

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