Furnace Installation in London, ON: A Guide to Choosing the Right Furnace
Prepare for winter with confidence. This guide will walk you through the key factors for choosing and installing a new furnace for your London, Ontario home.
In London, Ontario, a reliable and efficient furnace is not a luxury — it's a necessity. A properly functioning heating system ensures your family's comfort and safety throughout our famously cold winters, where temperatures regularly drop below -20°C. But how do you know when it's time to replace your old furnace? This buyer's guide will help you identify the signs and make an informed decision on your new furnace installation.
Is it Time for a New Furnace? Key Signs You Need a Replacement
Your furnace often gives you clues that its time is running out. Look out for these warning signs:
Age of Your Furnace
Most furnaces have a lifespan of 15-20 years with proper maintenance. If your unit is older than 15 years, it may be less efficient (operating at 80% AFUE or lower) and more prone to costly breakdowns. A new 96% AFUE furnace will save you 15-20% on heating bills immediately.
Rising Energy Bills
A sudden or gradual increase in your heating bills without a change in usage could mean your furnace is losing efficiency and working harder to heat your home. A 5-10% increase year over year is a red flag that your furnace is failing.
Frequent Repairs
If you're calling for furnace repairs year after year, the money spent on fixing an old unit ($500-$1,000 annually) could be better invested in a new, reliable system with a warranty. The "50% rule" — if a repair costs 50% or more of a new furnace, replace it.
Strange Noises
Loud banging (delayed ignition), rattling (loose components), squealing (blower motor issues), or clicking (ignitor failure) are not normal and can indicate serious internal problems requiring immediate attention.
Uneven Heating
If some rooms are warm while others are cold, your furnace may be struggling to distribute heat evenly, or its capacity may be insufficient for your home's needs. An undersized furnace runs constantly and never keeps up.
Yellow Burner Flames
Your furnace burner flames should be blue. Yellow or flickering flames indicate incomplete combustion, which can produce carbon monoxide — a deadly, odorless gas. This requires immediate professional inspection.
Choosing the Right Furnace for Your London Home
Once you've decided to replace your furnace, the next step is choosing the right one. Here are the most important factors to consider:
Fuel Source
Natural gas is the most common and cost-effective option for London homes due to Enbridge's reliable infrastructure. Propane is an alternative for homes without gas access ($3,900 for a 96% AFUE propane furnace). Oil and electric are less common and typically more expensive to operate.
Energy Efficiency (AFUE Rating)
AFUE measures how efficiently a furnace converts fuel into heat. Standard-efficiency furnaces are 80% AFUE. High-efficiency furnaces are 90-98.5% AFUE. Choose 96% or higher for maximum savings. A 96% furnace saves 15-20% on heating bills compared to 80% models.
Proper Sizing (Heat-Loss Calculation)
Correct furnace sizing is critical. A unit that is too small runs constantly and fails to heat properly. A unit that is too large "short-cycles," leading to wear, inconsistent temperatures, and wasted energy. We perform a professional heat-loss calculation (Manual J) to ensure perfect sizing.
Furnace Features (Single vs Two-Stage vs Variable)
Single-stage: runs at 100% or off — budget-friendly but temperature swings. Two-stage: runs at 65% most of the time — quieter, more even temps. Variable-speed: adjusts continuously — best comfort and efficiency, highest cost. For most London homes, two-stage offers the best value.
Furnace Installation Cost Breakdown by Brand & Efficiency
Abdullah Ghzail – Owner & Lead TSSA-Certified HVAC Specialist
"After hundreds of furnace installations across London, I've seen every mistake homeowners can make — and the most common is buying based on price alone or trusting a contractor who skips the heat-loss calculation. A furnace is a 15-20 year investment. Spend the extra time to get multiple quotes, ask for load calculations, and verify TSSA certification. The cheapest quote often becomes the most expensive in the long run through poor workmanship, incorrect sizing, and frequent repairs. We include a free heat-loss calculation with every estimate — no exceptions."
What London Homeowners Say About Their New Furnace Installations
"This buyer's guide was incredibly helpful. I had no idea about AFUE ratings or heat-loss calculations. Abdullah recommended a two-stage Lennox for our home near Masonville after doing a proper Manual J calculation — no one else did that. The furnace runs quietly on low speed 90% of the time, our home stays perfectly warm, and our gas bill dropped $50/month. Installation took one day and they cleaned up everything. Highly recommend reading this guide before buying."
— Mist B. London ON · December 2025
"Our furnace was 22 years old and we knew it was time. I followed this guide step by step. Got quotes from three companies — only Hawana did a proper heat-loss calculation. Everyone else just asked for our square footage and guessed. Abdullah determined our 1,700 sq ft home needed 60,000 BTUs, not 80,000 like others quoted. The smaller, properly sized furnace cost less upfront and saves us $40/month on gas. This guide saved us thousands."
— Stone T. London ON · November 2025
"The section on variable-speed furnaces convinced us to upgrade. Abdullah installed a Carrier 98% variable-speed furnace in our drafty Old North home. The difference is incredible — no more cold spots, the fan runs continuously at low speed keeping air filtered, and our gas bill dropped $70/month compared to last winter. Yes, it cost more upfront ($5,200), but the comfort is worth every dollar. This guide is essential reading before any furnace purchase."
— Birch K. London ON · October 2025
Furnace Buyer's FAQ — 2026
Most standard furnace installations can be completed in a single day, typically between 4 to 8 hours, depending on the complexity of the job. Converting from an 80% to a 96% AFUE furnace requires new PVC exhaust venting, which may add 2-4 hours. Ductwork modifications or challenging access can extend installation time. We provide a clear timeline in your written estimate.
Yes. Upgrading from an 80% AFUE furnace to a 96% AFUE furnace can reduce your heating costs by 15-20% or more. For the average London home spending $1,500-$2,000 annually on heating, that's $225-$400 saved each year. After Enbridge rebate ($650), net cost can be as low as $2,750 for a Goodman 96% furnace, with payback in 3-5 years through energy savings alone.
A heat-loss calculation (Manual J) determines the amount of heat your home loses in a given period. It considers square footage, insulation levels, window types, air sealing, orientation, and local climate. This professional assessment ensures your new furnace is perfectly sized — not too small (runs constantly, never heats properly) and not too large (short-cycles, wastes energy, fails prematurely). Never trust a contractor who skips this step.
Replace your furnace if: it's over 15 years old (most last 15-20 years); your energy bills are rising without increased usage; you're calling for repairs frequently (costing 50%+ of a new unit's price); you hear strange noises (banging, squealing, rattling); your home has uneven heating; or you see yellow flames (should be blue). A new furnace pays for itself through energy savings and avoided repairs.
Choose 96% AFUE or higher for maximum savings. The minimum standard in Canada is 90%, but high-efficiency furnaces with 95-98% AFUE provide 15-20% savings on heating bills compared to 80% models. For London's cold winters, 96% AFUE is the sweet spot for value and efficiency. Premium 98% models offer slightly higher savings but cost $500-$1,000 more upfront with a longer payback period.
Goodman offers excellent value with standard features and a good warranty — ideal for budget-conscious homeowners ($3,400-$4,000). Lennox and Carrier are premium brands with advanced features like variable-speed blowers and quieter operation — they cost 20-30% more ($4,200-$5,500) but offer superior comfort and efficiency. We install all three and recommend based on your budget and expectations. All have 10-year parts warranties when registered.
Furnace size is measured in BTUs (British Thermal Units). A 1,500-2,000 sq ft home typically needs 60,000-80,000 BTUs. A 2,000-2,500 sq ft home needs 80,000-100,000 BTUs. A 2,500-3,000 sq ft home needs 100,000-120,000 BTUs. Never guess — we perform a proper heat-loss calculation to determine the exact size your home needs. Incorrect sizing wastes energy and reduces equipment lifespan.
Natural gas is the most common and cost-effective option for London homes due to Enbridge's reliable infrastructure and competitive rates. Propane is an alternative for homes without natural gas access ($3,900 for a 96% AFUE propane furnace). Oil and electric furnaces are less common and typically more expensive to operate. Most London homeowners choose natural gas high-efficiency furnaces for the best ROI.
Yes. Furnace replacement and new installation require a permit from the City of London. A professional TSSA-certified contractor handles all permitting and inspections for you. Never hire a contractor who suggests skipping permits — it's illegal, unsafe, voids warranties, and can cause issues when selling your home. We manage all permits and schedule inspections so you don't have to worry.
Furnace installation costs in London range from $3,400-$5,500 depending on brand, AFUE rating, and features. A standard 96% AFUE Goodman starts at $3,400 installed. A two-stage 96% AFUE Lennox is $4,200-$4,800. A variable-speed 98% AFUE Carrier is $5,000-$5,500. After Enbridge rebate ($650), net costs drop to $2,750-$4,850. Get a free quote for your specific home. Prices include removal of old unit and all necessary venting materials.
Ready for a New High-Efficiency Furnace?
Don't wait for your old furnace to fail during a cold snap. Contact us today for a free estimate and professional installation in London, Ontario. We include a free heat-loss calculation with every quote.
📞 (647) 550-4220
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