Furnace Replacement Quotes in London, ON

London furnace prices at a glance

Standard gas furnace: $4,000 to $6,500single-stage burner at 95 to 96% AFUE
Two-stage gas furnace: $5,500 to $8,00096% AFUE, ECM blower
Furnace and AC together: $8,000 to $15,000Both replaced in one visit
Repair visit: $100 to $200Diagnostic before any parts

A furnace replacement in London typically costs $4,000 to $6,500 for a standard high-efficiency model and $5,500 to $8,000 for a two-stage one, installed and before HST.

The age of the house decides where you land. Century homes in Old North, Wortley Village and Old East Village sit higher because of chimney venting, older ducts and tight basements. Newer homes in Hyde Park, Byron and Lambeth are more often a straight swap, though the furnace and AC usually went in together, so many owners price both.

These are typical ranges, not quotes. The free furnace quotes arranged through this site come in writing, after a visit to your home.

London at a glance

Natural gas: Enbridge Gas
Electricity: London Hydro
Building permits: City of London. Needs depend on the job, so check with the city before work starts.
Winters: Near the snowbelt east of Lake Huron; lake-effect squalls can drop heavy snow fast.
Housing: Century homes near downtown, postwar suburbs, newer north and south ends.

Checked October 2026. Nearby towns have their own building departments.

How your part of London shapes the quote

Typical patterns, not rules. Every house gets its own visit and its own quote.

Add-on prices are typical Ontario ranges before HST, reviewed October 2026.
Home type	Where you see it	What often comes up	What it can add
Century homes	Old North, Wortley Village, Old East Village	Chimney venting, a water heater left on the chimney, patched ducts, narrow side yards	Venting or liner $300 to $1,500; ducts $500 to $3,000+
Postwar and 1970s homes	Between the core and the newer edges	Original ducts, central air added later, furnaces in finished basements	Condensate pump $150 to $350
Newer builds	Hyde Park, newer parts of Byron, Lambeth	Builder-grade furnace and AC aging out together	Furnace and AC $8,000 to $15,000

Century homes: three things to settle before you sign

In a hundred-year-old London house, the furnace is the easy part. These three items decide whether the quoted price is the price you pay.

Where the new furnace vents
A high-efficiency furnace vents through an outside wall with PVC pipe, clear of windows, doors, the gas meter and walkways. On a narrow downtown lot that can rule out the obvious spot. The route belongs on the quote.
What happens to the water heater
Take the furnace off the chimney and a gas water heater can be left alone in a flue that is now too big for it. The usual fix is a liner or a different water heater. Get it written into the quote.
Whether the ducts can carry the air
Old ducts were often patched over the decades. If you want central air or a heat pump too, ask whether the ducts were measured and whether changes are included.

Snow, vents and no-heat calls

A high-efficiency furnace breathes through two PVC pipes on an outside wall. If snow or ice blocks either one, the furnace shuts itself off.

That makes vent height a London question. Lake-effect snow and drifting can bury pipes that sit too low, and a blocked vent is a common reason a furnace stops after a storm. Settle the exit point at quote time.

Ask how high the pipes will sit above the usual snow depth
Avoid spots under a roof edge that sheds snow, in drift corners, or where plowed snow lands
After a big snowfall, gently clear both pipes. Still no heat? Book a repair

Request a furnace repair

1Exhaust and intake pipes. The furnace needs both clear to run.
2Clearance above the snow. The installation instructions set a minimum height above grade and the expected snow level.
3Too low. A pipe in the drift zone gets blocked and the furnace shuts off.

Simplified drawing, not to scale. Exact clearances come from the manufacturer and the gas code.

Repair or replace?

A one-part repair on a younger furnace is usually worth doing. Igniters, flame sensors and pressure switches are the usual no-heat culprits.

Replacement makes more sense when the furnace is near the end of its typical life, repairs keep coming back, or the technician finds a cracked heat exchanger. Unsure? Choose Not sure yet in the form and ask for a straight answer during the visit.

Furnace repair in detail Furnace replacement quotes

Diagnostic or service call: $100 to $200
Hot surface igniter: $250 to $450
Flame sensor clean or replace: $150 to $300
Pressure switch: $250 to $450
Control board: $500 to $1,100

Typical Ontario repair prices including parts and labour, before HST. Reviewed October 2026. A diagnostic visit usually comes first.

Want a written number for your London home, from a company that has seen the house?

Get A Free Quote

What a London quote should include, and when to book

Furnace brand, model number, AFUE and BTU input, plus the AC model and SEER2 if included
A heat loss calculation (CSA F280), not the old unit's size
The vent route and exit height, with the snow line in mind
The plan for a water heater left on the chimney
Who arranges any permit, the TSSA registration number for gas work, warranty, deposit and install date

Timing. Furnace schedules fill in the first cold spell of the fall, and AC work peaks in the first heat wave. Spring and early fall give you the most install dates and time to compare. No heat? Choose Urgent in the form and expect a repair visit first.

Comparing quotes? Line them up item by item. A lower price that leaves out venting or duct work is not cheaper. The quote checker tests any price against typical ranges for the same scope.

St. Thomas, Komoka, Strathroy, Ilderton and Dorchester

Requests from outside the city work the same way; your postal code finds a participating company that serves your area. Permits go through your own municipality. Rural homes off the gas network heat with propane, oil or electricity, so say so in the form.

St. Thomas: City of St. Thomas.
Komoka and Ilderton: Municipality of Middlesex Centre.
Strathroy: Municipality of Strathroy-Caradoc.
Dorchester: Municipality of Thames Centre.

Furnace quotes in Kitchener Furnace quotes in Hamilton All city quote pages

Common questions

Straight answers. If yours is not here, the company can answer it during your free estimate.

How much does furnace replacement cost in London, Ontario?

A standard high-efficiency gas furnace typically costs $4,000 to $6,500 installed, before HST, and a two-stage model $5,500 to $8,000. Replacing the furnace and central air together typically runs $8,000 to $15,000. Century homes often land higher because of venting and duct work. Your written quote after the visit is the real number.

Why do century homes in Old North or Wortley Village cost more?

Mostly venting and ducts. A high-efficiency furnace cannot use the old chimney, so new PVC venting has to find a legal exit, often on a narrow lot. A gas water heater left on the chimney may need a liner, and older ducts may need changes for central air. Each should be a line on the quote.

My furnace stopped after a snowstorm. What should I check?

Look at the two PVC pipes on the outside wall. If snow or ice blocks either one, the furnace shuts itself off. Clear them gently, then try the thermostat again. If it does not restart, request a repair. If you smell gas, leave the house right away and contact Enbridge Gas from outside.

Should I replace my furnace and AC together?

If both are original to a newer north or south end home, it often makes sense: one visit, matched equipment and one warranty start date. Together they typically cost $8,000 to $15,000 before HST. If the AC is much newer and working well, ask for a furnace-only price too and compare.

Keep going

Get a real number for your London home

Answer a few quick questions. A participating local HVAC company will confirm the details and book a free in-home estimate.