A Calgary home inspection covers a lot of ground in a few hours: the roof, foundation, electrical, plumbing and more. The furnace usually gets a quick look: the inspector turns it on, sees that it heats, and notes its age. But the heating system is one of the most expensive parts of any Calgary home to replace, and in this climate it isn’t optional. This checklist helps you look closer before you remove your conditions.
Why HVAC Matters More in Calgary
Calgary furnaces run for most of the year, through long winters, cold snaps and Chinook temperature swings. A furnace that’s tired in a milder city may simply fail here in January. Replacing one after you move in costs thousands of dollars, so it’s worth knowing what you’re buying.
Step 1: Find the Age of Every System
Look for the manufacturer’s label inside the furnace door, on the side of the outdoor air conditioner and on the hot water tank. The manufacture date is often printed directly, or built into the serial number. As a rough guide in Calgary:
- Gas furnace: about 15 to 20 years
- Central air conditioner: about 12 to 15 years
- Gas hot water tank: about 8 to 12 years
A furnace or tank near the end of that range isn’t a deal-breaker, but it is a cost to plan for.
Step 2: Check What Kind of Furnace It Is
Look at the venting. Two white plastic pipes running to an outside wall usually mean a high-efficiency furnace. A metal flue going up through the roof or into a chimney usually means an older mid-efficiency furnace. Replacing a mid-efficiency furnace means adding new plastic venting and a condensate drain, and sometimes a chimney liner for the water heater, which adds to the cost.
Every new gas furnace sold in Canada today is at least 95% efficient, so an older unit will cost more to run.
Step 3: Look for These Red Flags
- Rust, water or white crust around the furnace base or the hot water tank
- Scorch marks or soot near the burner area
- A yellow or flickering burner flame instead of steady blue
- Loud banging, squealing or rattling when the furnace starts
- Taped or disconnected vent pipes, or white pipes outside that end close to the ground
- A very dirty filter, which suggests the system hasn’t been looked after
- Rooms that stay cold or a basement that never warms up
- No carbon monoxide alarm near bedrooms
Step 4: Check the Air Conditioner
If the home has central air, find its age and refrigerant type on the outdoor unit’s label. Units that use R-22 refrigerant are older, and R-22 is no longer produced, so even a small leak can be expensive to fix. Many Calgary buyers plan to replace those units, or swap them for a heat pump, within a few years.
Step 5: Ask the Seller for These Documents
- Service and tune-up records for the furnace and AC
- Installation invoices and any registered warranties (many manufacturers require registration within 60 or 90 days, and some warranties don’t transfer)
- Recent utility bills, to see what heating actually costs
- Confirmation that recent furnace, AC or water heater work was done with a permit
In Calgary, furnace installations and replacements require a permit, and gas work must be done by a qualified gas fitter. The City of Calgary heating, cooling and ventilation permit page explains which permits apply. Unpermitted work can cause problems with insurance or a future sale.
Calgary Details Buyers Often Miss
- Basement development: a finished basement added years after the house was built may have too few heat runs or no cold-air return, which leaves it chilly. Ask whether the basement was permitted and check that every room has a supply vent and some way for air to return.
- Older inner-city homes: houses in established neighbourhoods may have original ductwork, undersized returns or an old chimney shared with the water heater. Replacing the furnace in these homes sometimes means extra venting work.
- Humidifier condition: many Calgary homes have a furnace-mounted humidifier. Check for rust, mineral build-up or water stains below it; a leaking humidifier can damage the furnace.
- Garage heaters: a gas heater in the garage is common here. It should have proper venting and clearances, and it counts as gas work that needs a permit.
- Heat pumps: if the home has one, confirm it’s a cold-climate model and that it’s paired with the furnace so the furnace takes over in deep cold.
Step 6: Consider a Dedicated HVAC Inspection
If the furnace is over 12 years old, the house has a history of repairs, or something on this list worries you, ask a licensed HVAC company to inspect it during your conditions period. A technician can check the heat exchanger for cracks, test for carbon monoxide, measure gas pressure and look at the venting, which a general inspector usually can’t.
Calgary Replacement Costs to Factor In
These are typical 2026 Calgary ranges published by local HVAC companies:
- New high-efficiency furnace, installed: about $5,500 to $11,000 (see this Calgary furnace installation cost guide)
- Central air conditioner, installed: about $5,000 to $8,500
- 50-gallon gas hot water tank, installed: about $2,100 to $2,400
- Whole-home humidifier, installed: about $525 to $650
Use these numbers when deciding whether to ask for a price reduction or a credit.
Using What You Find in Negotiations
An old but working furnace is common in Calgary resale homes and usually isn’t a reason to walk away. Instead, get a written quote for furnace replacement and ask your realtor whether a credit or price adjustment makes sense. Signs of a cracked heat exchanger, carbon monoxide or water damage are more serious and should be resolved before you remove conditions.
After You Move In
- Change the furnace filter on day one.
- Book a furnace tune-up before your first winter, even if the inspection was clean.
- Test or install CO and smoke alarms on every level.
- Add a whole-home humidifier if the house doesn’t have one; Calgary’s winter air is very dry.
- Consider a maintenance plan so yearly service happens automatically.
If something fails in your first winter, Purcell Heating & Air offers 24/7 furnace repair in Calgary and HVAC services across the city.
Frequently Asked Questions
Does a home inspection in Calgary check the furnace?
Yes, but usually at a basic level. A general inspector typically checks that the furnace runs, notes its age and looks for obvious problems. They usually don’t test for heat exchanger cracks, gas pressure or carbon monoxide, which an HVAC technician can.
How old is too old for a furnace in a house I’m buying?
There’s no hard cut-off, but most Calgary furnaces last about 15 to 20 years. A furnace over 15 years old is worth inspecting closely and budgeting to replace, especially if it’s a mid-efficiency model or has needed several repairs.
Can I negotiate the price because of an old furnace?
Often, yes. Get a written replacement quote and discuss it with your realtor. Sellers may offer a credit or price reduction, particularly if the furnace is near the end of its life or the inspection found problems.
Should I worry if the house has no air conditioning?
Not necessarily. Many Calgary homes don’t have central air. If the furnace and ductwork are in good shape, adding an air conditioner or a heat pump later is usually straightforward.
