Should you repair or replace your furnace or air conditioner?

Updated November 10, 2026 · KeystoneProGuide editorial team

How do you decide whether to repair or replace?

Start with three facts about your system: its age, the price of the repair in front of you, and whether it has been keeping the house comfortable. ENERGY STAR's guidance turns on the first and the third. It suggests considering replacement when a heat pump or air conditioner is more than 10 years old, or a furnace or boiler more than 15, and particularly when the equipment needs frequent repairs and your energy bills are going up.

Below those ages, ENERGY STAR's guidance gives no reason to replace equipment that is keeping the house comfortable. Above them, a large repair is the moment to price the alternative.

What do repairs cost compared with replacement?

The national cost surveys give a sense of scale. HomeAdvisor reports an average HVAC repair of $350, with jobs from $100 to $3,000, and an average furnace repair of $318. A few parts it prices:

Against those, HomeAdvisor puts a complete new system, furnace and central air together, at about $7,500 on average, with most homeowners paying $5,000 to $12,500. Angi gives a national average of $4,814 for a new furnace alone.

So an ignitor on a furnace that has not yet reached 15 years is simply a repair. A compressor on an air conditioner past ENERGY STAR's 10-year mark is a decision.

When does the age of the refrigerant matter?

If your air conditioner or heat pump is old enough to use HCFC-22, it matters a great deal. The U.S. Environmental Protection Agency says there has been no production or import of HCFC-22 since 2020, while some use continues for servicing existing equipment. Any recharge relies on refrigerant that already exists. Before approving a leak repair on such a system, ask what the refrigerant will cost and whether the leak can be found and fixed, or whether you would be paying to refill a system that will lose its charge again.

How much would new equipment save?

ENERGY STAR gives figures for its certified equipment, measured against standard models, not against your particular unit:

• Gas furnaces in the northern states, including Pennsylvania: up to 18 percent more efficient than baseline models, saving $160 a year.
• Oil furnaces: up to 4 percent more efficient, saving about $90 a year.
• Gas boilers: about $780 saved over the life of the product; oil boilers $200.
• Replacing old heating and cooling equipment generally: depending on where you live, nearly $140 a year off the energy bill.

These compare certified models with standard new ones. ENERGY STAR does not publish a figure for how your own unit compares, so treat them as a guide, not a promise.

What else could be causing the problem?

Sometimes not the equipment. ENERGY STAR warns that before investing in a new system you should deal with the big air leaks in the house and the duct system, because sometimes these are the real sources of the problems. Its list of signs points the same way: rooms that are too hot or too cold can come from duct problems or poor insulation, and excessive dust from leaky ducts.

It also says installation quality matters as much as the equipment. Poor airflow and a wrong refrigerant charge can reduce efficiency, and improper installation can cut it by up to 30 percent. A replacement is only an improvement if it is installed properly.

What questions settle the decision?

Ask the contractor who diagnoses the problem:

1. What exactly failed, and what will the repair cost, in writing?
2. Is the part still available for this model, and is it covered by any remaining warranty?
3. What other parts are close to failing, based on what you saw today?
4. For an air conditioner or heat pump: what refrigerant does it use, and is there a leak?
5. If I replace instead, what size would you install, and how did you work that out?

Then get a replacement quote from at least one other company. A contractor who has already diagnosed a failure is not the only one who can price the replacement.

What if the system fails in winter and money is tight?

Pennsylvania has an emergency route. The state's LIHEAP Emergency Services program, run with local weatherization agencies, can pay for heating system repair and for replacing a heating system that cannot be repaired, for eligible households with no heat or in danger of losing it. Apply through your county assistance office.

There is no longer a federal tax credit to count on: ENERGY STAR says the credits for efficient furnaces, boilers, air conditioners and heat pumps ended on December 31, 2025.

Full price ranges are in the cost guide, and the signs that send you to this decision are in signs your system needs a professional. Contractors are listed on the HVAC contractors directory page.

Sources

1. When is it time to replace?, ENERGY STAR
2. Heat & Cool Efficiently, ENERGY STAR
3. How Much Does HVAC Repair Cost?, HomeAdvisor
4. How Much Does It Cost to Repair a Furnace?, HomeAdvisor
5. How Much Does It Cost to Install or Replace an HVAC System?, HomeAdvisor
6. How Much Does a New Furnace Cost? [2026 Data], Angi
7. Phaseout of Class II Ozone-Depleting Substances, U.S. Environmental Protection Agency
8. Furnaces, ENERGY STAR
9. Boilers, ENERGY STAR
10. HVAC Quality Installation, ENERGY STAR
11. Pennsylvania LIHEAP Emergency Services Program, Pennsylvania Department of Community and Economic Development
12. Federal Tax Credits for Energy Efficiency, ENERGY STAR