Should I Replace My Air Conditioner And Furnace At The Same Time?




We can all agree that replacing an air conditioner and a furnace at the same time is expensive.

But the only way to ensure that your air conditioner performs at its rated efficiency is by replacing your furnace at the same time.

The problem is that the average lifespan of a central air conditioner is about 15-20 years while the average lifespan of a furnace is about 15-30 years. In general, furnaces last longer than air conditioners — sometimes over twice as long.

In this article, we’ll explain why replacing your air conditioner and furnace at the same time (in order to install a “matched system”) is probably the best choice. We’ll also discuss why you may NOT want to replace both systems at the same time.

Why you should replace your air conditioner and furnace at the same time

The blower (aka fan), which is normally a part of the furnace, is used to blow conditioned air throughout your home.

This blower is necessary to produce the proper airflow for the evaporator coil and heat exchanger to operate at their rated efficiencies. It is also what pushes the air throughout your house.

A split air conditioner is composed of two main units:

  • The Outdoor Unit contains the condenser coil (1) and compressor (2)
  • The Indoor Unit contains the evaporator coil (3) and air handler/blower (4)

While it is always necessary to replace both air conditioning components at the same time (in a split system), it’s not always necessary to replace both AC components and the furnace.

Still, the air conditioner will need to use the blower motor, which is why the only way to guarantee the new air conditioner will perform at its rated efficiency is to replace the heating system at the same time.

For instance, if you choose a high-efficiency air conditioner with a SEER rating above 16 and your furnace has an old blower motor, you are using a mismatched system which will sacrifice some efficiency. Although it’s possible to mix and match the systems, it’s not recommended, especially if the furnace is over 15 years old.

Replacing the outdoor unit while leaving the old blower will result in lower efficiency and could result in premature failure and other problems.

Note: You should always replace both air conditioning components (condenser/compressor and evaporator coil) at the same time. This does not necessarily mean it always makes sense to replace the AC and the heating system at the same time.

Keep in mind that replacing a furnace on its own will cost around $2,000 to $5,000. Adding a furnace during your air conditioner replacement will cost a lot less, around $1,000 to $3,000.

The only time it really makes sense to wait to replace your furnace is if it is less than 10 years old. This way, the furnace will most likely last until the next time your air conditioner needs to be replaced.

When to replace air conditioner and furnace at the same time:

  • If your furnace is over 15 years old.
  • If you are buying a high-efficiency air conditioner with SEER above 16.
  • If the installation is complicated.
  • If you don’t want to worry about HVAC repairs and replacements for a while.

When NOT to replace your furnace and air conditioner at the same time:

There’s really only one instance when you should consider waiting to replace your furnace at the same time as your air conditioner — if the furnace is less than 10 years old.

In most cases, if the furnace is less than 10 years old, you are probably better off waiting until your next air conditioner replacement. This is because the furnace will probably last 20-30 years, while air conditioners should be replaced every 10-15 years or so.

Get a Free Estimate

In the end, the decision is yours, but we highly recommend speaking with an honest contractor first before making the final decision. Having a blower that matches your new air conditioner is necessary to maximize your system’s efficiency, to reduce your energy bills, and to extend the life of your new system.

To see how much it would cost to just replace the air conditioner versus replacing the entire heating and cooling system, contact Service Champions for a free estimate.

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