When should I replace my furnace instead of repairing it?
E&R Construction · Published October 15, 2026
The short answer
Consider replacing it when the furnace is around 15 years old or more, repairs are becoming frequent or expensive, or the house heats unevenly despite repairs. A newer, more efficient furnace can also lower your heating bills.
In an Ottawa winter the furnace is not something you want to gamble on. Here is how to tell whether to keep repairing yours.
Age
Many furnaces last around 15 to 20 years. The age is usually on the label inside the furnace door. As a furnace nears the end of that range, each repair buys less time.
Repair history
One repair on a newer furnace is normal. Several repairs in a few years, or a single repair costing a large share of a new furnace, are signs that replacing it is the better investment.
Comfort and bills
- Rooms that are much colder than others.
- The furnace running constantly, or turning on and off often.
- Heating bills rising without a change in how you use the house.
Noises and smells
Banging, rattling or squealing can mean worn parts. If you ever smell gas, leave the house right away and call your gas utility's emergency line or 911 from outside.
Safety
Every home with a fuel-burning furnace should have working carbon monoxide alarms. Replace the batteries regularly and test the alarms.
Replacing the air conditioner at the same time
The furnace fan also moves cool air in summer, so if your air conditioner is old too, it can make sense to replace both together.
See our heating and cooling page, or request a quote.
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