Signs your furnace or air conditioner needs replacing

Furnaces and air conditioners do not last forever, and replacing one before it fails in winter or midsummer lets you shop calmly instead of in a rush.

The short version: age, rising repair bills, uneven comfort, strange noises and higher energy bills are signs to start planning. Get several quotes and compare efficiency, not just price.

How long they last

Lifespan depends on the type, the maintenance and how hard the system works. Many furnaces last 15 to 20 years or more, and air conditioners often 10 to 15 years, but manufacturer information and your technician's judgment matter more than any single number.

Signs your furnace needs attention

• It is more than about 15 years old.
• Repairs are becoming frequent or costly.
• Heating bills are climbing without a change in use.
• Some rooms are too hot or too cold.
• Strange noises, such as banging or squealing.
• Frequent cycling on and off.
• Yellow or flickering pilot or burner flame, or soot. This can mean a CO risk, so call a professional immediately.

Signs your air conditioner needs attention

• Warm air or weak airflow.
• Ice on the unit or lines.
• Humidity or musty smells.
• Loud or rattling noises.
• Frequent breakdowns or a refrigerant leak.

Repair or replace

A common guideline is to compare the repair cost with replacement, especially when the unit is old. If a repair is large and the equipment is near the end of its life, replacing it often makes more sense. A technician can give you a recommendation, but get a second opinion.

Efficiency and options

Higher-efficiency furnaces use less fuel. Heat pumps provide both heating and cooling and may reduce energy costs. The federal Canada Greener Homes grant and loan are closed. A new federal heat pump rebate was announced on October 8, 2026, with launch aimed at early 2027, so check current federal, provincial and utility programs before you buy.

Choosing a contractor

• Get at least three written quotes.
• Ask for load calculations so the equipment is sized correctly.
• Check licensing, insurance and warranty terms.
• Compare brands, efficiency ratings and installation details.

Example

A 20-year-old furnace needing a $900 repair is a good moment to get replacement quotes. Compare what the repair would buy you with the cost of a new unit.

Prices vary by region, so get quotes.