Skip attic units. If you’re thinking long-term comfort during heatwaves, a fully integrated solution that moves treated air through existing ductwork is the most practical route. It keeps your space consistent, especially in multi-level homes, and helps avoid the uneven cooling that standalone systems struggle with. Some people attempt partial setups, but those tend to underperform and overcomplicate maintenance.
You’ll need a unit matched to your square footage. For an average 1,500–2,000 sq ft home, that typically means around 2.5 to 3 tons of cooling capacity. Not oversized, not undersized–just right. Too large, and it cycles too quickly. Too small, and it’ll never catch up on those 30°C July afternoons. Local suppliers in Alberta often recommend SEER 13–16 for a balance between upfront cost and energy use. I went with a 15 myself. It seemed reasonable.
Expect to dedicate a weekend, minimum. Maybe more if it’s your first try or you’re juggling work. The toughest part? Probably the line set routing and wiring. Not impossible, but awkward if your furnace room is tucked into a tight corner like mine. You’ll want to map everything beforehand and double-check your breaker panel has space for a 240V double-pole breaker. If not, you’re adding electrical work into the mix.
Don’t skip the permit. Yes, it’s paperwork. But in Calgary, it’s required–especially if electrical and refrigerant connections are involved. Inspectors aren’t unreasonable, but they will check your grounding, bonding, and clearances. You don’t want to be ripping it apart a month later because something didn’t pass. Besides, it’s safer this way. I get the temptation to rush through it, but it rarely ends well.
Choosing the Right Unit for Calgary’s Climate and Home Sizes
Pick a model rated for at least 13 to 16 SEER. Higher is better, sure, but there’s a point where the extra cost doesn’t really pay back in Calgary’s shorter cooling season. You’re not running the system for nine months–three, maybe four, and even then, not every day.
Go too small, and the unit will run constantly trying to catch up. Too large, and it’ll short cycle, starting and stopping more than it should. That wears it out fast and doesn’t remove humidity well. For a 1,500 sq ft home, you’re probably looking at something between 2 to 2.5 tons. But don’t guess–get a proper load calculation. Square footage alone isn’t enough. Insulation, windows, shading, even how many people live there–it all matters.
In older neighbourhoods like Mount Pleasant or Renfrew, homes often have quirks–partial basements, additions, oddly shaped rooms–that mess with airflow. A variable-speed compressor can help even things out, though it’s pricier. Worth it? Maybe. Depends how uneven the cooling is in your place.
If you’re upgrading from a window unit or nothing at all, the quiet alone is a game changer. But don’t just focus on brand names or BTUs. Think about what kind of summer you usually get. Last July? Hot, sure, but not unbearable. Year before that? Different story. So if you’re stuck choosing between a cheaper single-stage or a mid-tier two-stage system, think about those heat waves–not averages.
And yes, Canadian winters are brutal, but don’t ignore the few really hot weeks. That’s when the unit has to deliver. You’ll notice if it doesn’t. Comfort isn’t just about temperature–it’s about how fast the system can adjust, how quietly it runs, and whether you can sit through dinner without it blasting on and off every five minutes.
Preparing Your Home: Electrical, Ductwork, and Permit Requirements in Calgary
Before anything else, check the electrical panel. You’ll need a dedicated 240-volt circuit with enough available amperage–most systems require at least 30 amps. If your panel’s maxed out, upgrading it could run a few thousand dollars, depending on the age and layout of your home. And if the panel’s tucked away in a finished basement or an awkward corner? Expect some extra labour costs to make everything accessible and code-compliant.
For ductwork, look at what’s already in place. Older homes in Calgary often have ducts sized for heating only, which means airflow might be too restricted. Undersized trunks or poorly placed returns can choke performance. It’s not always obvious until the equipment starts running, so a manual J and D calculation is worth the time, even if it seems like overkill. Sometimes a small tweak–like adding a return in the master bedroom–makes a noticeable difference. Or, in tighter homes, you may need to run new lines to avoid major temperature swings between floors.
Permits? Yes, you need them. For anything involving refrigerant lines and electrical connections, the City of Calgary requires mechanical and electrical permits. Skipping them isn’t just risky–it can delay future home sales or trigger issues with insurance. Apply online through the city’s ePermit system. It’s usually straightforward, though timelines vary. Mechanical inspections often get scheduled within a week, but electrical can take longer, especially during peak renovation season. Double check that your contractor, if you’re working with one, is licensed and listed on the city registry–inspectors have been known to flag installs done by unverified trades.
One more thing–noise regulations. If you’re placing an outdoor unit near a neighbour’s window or fence line, Calgary bylaw officers can investigate if the unit’s too loud. Sound levels must stay under 65 decibels at the property line. You might need to rethink placement or add a sound barrier. It’s not just about keeping the peace–it’s about not having to rip things out later.
Step-by-Step Installation Process with Local Safety Codes and Tools
Mount the outdoor compressor unit at least 1 metre from any gas meter or dryer vent – that’s a must under Alberta Building Code. You’ll need a level pad, preferably concrete or a composite base, to reduce vibration and keep it stable during thaw-freeze cycles.
Run the refrigerant lines through a properly sealed wall sleeve. Drill a hole with a slight downward angle to prevent moisture ingress. Use insulated copper tubing, and don’t skimp on the insulation – frost damage is real during Calgary winters.
Indoor Setup and Electrical Work
Position the evaporator coil directly above the furnace plenum. If the existing ductwork is outdated, you might run into clearance issues – measure twice. Seal all joints with UL 181-rated foil tape, not duct tape. It might sound picky, but inspectors will flag that.
For electrical, you’ll need a dedicated 240V breaker. Use an approved whip kit to connect the outdoor unit, and double-check GFCI protection. And yes, grounding is mandatory. Don’t assume the old panel is up to current specs – I had to replace mine completely because the neutral wasn’t properly bonded.
System Charging and Code Compliance
After pressure testing with nitrogen and vacuum-pulling to 500 microns or lower, charge the system based on manufacturer specs – not by guesswork. A digital manifold gauge saves a lot of second-guessing here. If you’re not certified to handle refrigerant, you’ll need to hire someone who is. It’s not just about getting caught – it’s about not botching the charge and wrecking a $3,000 compressor.
Final checks? Confirm airflow meets the minimum 350 CFM per ton and verify with a manometer that static pressure stays within 0.5 in. w.c. range. Anything higher and you’re straining the blower motor. Not something you want to find out in January.
Contact “Calgary Air Heating and Cooling Ltd” For More Information:
Address
95 Beaconsfield Rise NW, Calgary, AB T3K 1X3
Phone
+1 403 720-0003
Hours of operation
Open 24 hours 7 days a week