Should we replace our 20-year-old furnace now or wait until it dies? Efficiency savings versus upfront cost?

A 20-year-old furnace in Calgary is approaching the end of its typical lifespan, and replacing it proactively rather than waiting for failure often makes financial sense — especially given our extreme winters where furnace failure means emergency replacement at premium pricing.

The Efficiency Case for Replacement

Your 20-year-old furnace likely operates at 80-85% AFUE (Annual Fuel Utilization Efficiency), while today's standard high-efficiency units in Calgary operate at 96%+ AFUE. This 10-15% efficiency improvement translates to real savings on your natural gas bills. With Calgary's long heating season (October through April), a typical home might save $300-600 annually on heating costs. Over a 15-20 year furnace lifespan, that's $4,500-12,000 in energy savings.

Calgary's Extreme Climate Factor

Calgary's brutal winters make furnace reliability critical. When temperatures hit -30°C during a January cold snap, you can't afford to wait for parts or schedule repairs. Emergency furnace replacements during peak winter demand often cost 20-30% more than planned replacements, and you'll have limited equipment options. Contractors are swamped during cold snaps, potentially leaving you without heat for days.

Current Replacement Costs vs. Repair Costs

High-efficiency furnace replacement in Greater Calgary typically runs $4,500-8,500 installed, depending on your home's size, ductwork condition, and equipment brand. Mid-efficiency units run $3,500-6,000. Meanwhile, major repairs on 20-year-old equipment (heat exchanger, blower motor, gas valve) can easily cost $1,500-3,000, with no guarantee other components won't fail soon after.

The Proactive Replacement Advantage

Replacing now gives you time to research contractors, compare quotes, and potentially schedule during shoulder seasons (spring/fall) when contractors offer better pricing and availability. You can also take advantage of utility rebates — ATCO and other Alberta utilities often provide rebates for high-efficiency furnace upgrades. The Canada Greener Homes Grant may also apply if you're doing multiple energy efficiency upgrades.

When to Replace vs. Repair

Replace if your furnace is 18+ years old, requires frequent repairs, has a cracked heat exchanger, or your heating bills have increased significantly. Also replace if you're planning other home improvements — coordinating furnace replacement with ductwork upgrades, basement finishing, or electrical panel upgrades can save money.

Next Steps

Get quotes from three licensed HVAC contractors for high-efficiency replacement. Compare the annual operating cost savings against your current unit, factor in available rebates, and consider financing options. Most contractors offer seasonal promotions in spring and fall. Given Calgary's climate and your furnace's age, proactive replacement is likely your smartest financial move.