132 Cartwright Ave, North York ON
Mon–Sat 8am–7pm · Sun 9am–5pm
Heat pump basics · how it works
What a heat pump is —
and how it actually works
A heat pump does not create heat the way a furnace flame or an electric element does. It moves heat that already exists, using the same refrigeration cycle as your fridge — just run in both directions. Here is the mechanics, explained plainly, from a Toronto contractor who installs and services these year-round.
The core idea
Heat pumps move heat. They do not manufacture it.
Every heat pump runs a closed refrigerant loop through four jobs: evaporate, compress, condense, expand. A refrigerant boils into vapor in one coil, absorbing heat from whatever air passes over it; a compressor squeezes that vapor, raising its pressure and temperature; the hot vapor gives up its heat in a second coil and condenses back to liquid; an expansion valve drops the pressure so it can absorb heat again. A reversing valve decides which coil is doing which job, so the same outdoor unit heats your home in January and cools it in July.
That distinction — moving heat instead of generating it — is why the efficiency math looks so different from a furnace. Burning gas or running an electric element is capped near 100% efficiency: one unit of energy in gets you, at best, one unit of heat out. A heat pump is not creating that heat from the electricity it consumes; it is using the electricity to relocate heat that is already sitting in the outdoor air. That is why it can deliver several units of heat for every one unit of electricity it uses — the electricity pays for compression work, not combustion.
It sounds counterintuitive that there is heat to extract from air that feels cold, but air above absolute zero still holds usable thermal energy — the colder it gets, the harder the compressor has to work to pull it out, which is exactly why cold-climate rated compressors matter for Toronto winters. See our heat pump services page for the equipment we install, or keep reading for the mechanical detail.
Toronto and GTA conditions are not mild-climate marketing charts. Design temperatures, humidity, older building stock, and mixed fuel strategies change how heat pump installation should be specified. We start with how you use the space — occupancy, hours, duct capacity, electrical service, and existing equipment — before recommending parts or a full replacement.
Homeowners, landlords, and facility managers call us when systems short-cycle, ice up, leave rooms uneven, spike utility bills, or fail on the first deep freeze or heat wave. Whether you need a same-week repair or a planned upgrade, we document findings and present repair-versus-replace paths with pricing you can compare.
Explore related hubs for heating, cooling, and commercial HVAC, or ask about rebates and incentives that may apply to high-efficiency equipment. Call 647 953-4252 with model numbers and symptoms so we arrive prepared.
What matters most for heat pump installation in the GTA
Right sizing, licensed gas/refrigeration work, and commissioning beat the cheapest sticker price. We verify airflow, safety devices, condensate paths, and controls so your system does not fail the first extreme week of the season. Ask us about dual-fuel, zoning, and rebate-eligible models during your quote.
The core components at work
- Refrigerant — a fluid engineered to boil and condense at low temperatures, carrying heat between coils
- Evaporator coil — where refrigerant absorbs heat from the air passing over it
- Compressor — squeezes refrigerant vapor, raising its pressure and temperature
- Condenser coil — where hot refrigerant releases heat into the space being heated
- Expansion valve — drops refrigerant pressure so it can absorb heat again
- Reversing valve — flips the whole cycle so one unit heats in winter and cools in summer
- Defrost cycle — briefly reverses to melt frost off the outdoor coil so it keeps absorbing heat
- Slower output on the coldest hours is normal compressor behaviour, not a fault
Practical sequence
How we approach heat pump installation
A structured process so you always know the next step.
01
Consult
Goals & constraints
02
Assess
On-site measurements
03
Compare
Repair vs replace
04
Schedule
Parts & access
05
Execute
Licensed install
06
Verify
Commission & teach
Where this fits
Common heat pump installation applications in Toronto & the GTA
Different buildings need different equipment paths. These are the scenarios we see most often.
01
Detached & semi-detached homes
Full replacements, dual-fuel strategies, and comfort fixes for older duct systems common across Toronto neighbourhoods.
02
Condos & townhomes
Compact footprints, quiet operation, and board-friendly installs where access and condensate matter.
03
Additions & renovations
Matching new loads without oversizing, including ductless zones where trunks cannot reach.
04
Light commercial
Retail, clinics, offices, and mixed-use spaces that need documented maintenance and predictable uptime.
05
Rental properties
Durable equipment choices, clear landlord options, and service plans that reduce emergency callouts.
06
Efficiency upgrades
High-AFUE / SEER2 / heat-pump paths with rebate paperwork guidance when programs apply.
How we apply this
Heat pump installation & service built on the mechanics
Understanding the refrigeration cycle is how we size, install, and troubleshoot systems correctly — not guesswork.
Cold-climate heat pump installation
Compressors and controls selected for real Toronto design temperatures, not mild-climate brochure numbers.
Heat pump services →Refrigerant circuit diagnostics
TSSA refrigeration-certified technicians test charge, pressures, and valve operation when performance drops.
Ducted & ductless equipment matching
The same refrigeration cycle, packaged differently — we match the format to your home's layout.
Dual-fuel / hybrid backup design
Furnace backup wired in for the hours when compression work outpaces what the compressor can efficiently deliver.
Maintenance & seasonal tune-ups
Coil cleaning, defrost checks, and refrigerant verification so the cycle keeps running the way it was designed to.
Book a tune-up →Additional heat pump installation support
Seasonal tune-ups, safety checks, filter guidance, and control adjustments that keep performance stable through GTA weather swings. Ask us to bundle maintenance with your install or repair visit.
Book a visit →Related services
See the mechanics installed correctly
Understanding the cycle is one thing — sizing and installing it for Toronto winters is another.
01
Heat Pumps GTA
Cold-climate heat pump installation, service, and hybrid backup design.
View heat pump services →FAQ
How heat pumps work — FAQ
Does a heat pump make heat, or just move it?
It moves it. Refrigerant absorbs heat on one side of the cycle and releases it on the other; the electricity you pay for mostly runs the compressor, not a flame or heating element. That is the whole reason a heat pump can be far more efficient than resistance heat.
How does the same unit heat in winter and cool in summer?
A reversing valve switches which coil is the evaporator and which is the condenser. Flip the valve, and the outdoor coil that was releasing heat starts absorbing it instead, and vice versa indoors.
Why does the outdoor unit sometimes look like it's steaming?
That is the defrost cycle. Frost naturally builds on the outdoor coil in cold, humid weather, so the system briefly reverses to melt it off before returning to normal heating — the "steam" is melting frost, and it is expected behaviour.
Can a heat pump still pull heat out of air that's below freezing?
Yes — there is still usable thermal energy in air well below 0°C. What changes is how hard the compressor has to work to extract and concentrate it, which is why cold-climate compressors and correct sizing matter for Toronto winters.
What's the difference between the compressor and the condenser?
The compressor is a component that pressurizes refrigerant vapor. The condenser is the coil where that hot vapor gives up its heat and turns back into liquid. The compressor does the work; the condenser is where the payoff happens.
Do I need to understand any of this to own a heat pump?
No — but it helps explain why output looks different on a mild October day versus a January cold snap, and why proper sizing and commissioning matter more for a heat pump than for a simple on/off furnace.
Who installs and services heat pumps in Toronto?
Toronto Air Systems — TSSA-licensed, refrigeration-certified technicians serving Toronto and the GTA. Call 647 953-4252 or visit contact us to talk through your home.
How much does heat pump installation cost in Toronto?
Cost depends on equipment capacity, brand, duct or piping complexity, electrical/gas upgrades, and whether you repair or replace. We provide written quotes after a site assessment so you can compare options fairly. Call 647 953-4252 for a visit.
Do you serve my area in the GTA?
Yes. We are based in North York at 132 Cartwright Ave and regularly serve Toronto, Mississauga, Vaughan, Markham, Scarborough, Etobicoke, Brampton, and nearby communities.
Are your technicians licensed?
Yes. Gas and refrigeration work is performed by TSSA-licensed technicians. We follow Ontario code practice for venting, refrigerant handling, electrical disconnects, and condensate management.
Want a heat pump engineered for how Toronto winters actually work?
Talk to TSSA-licensed, refrigeration-certified technicians about a system built for your home. Call 647 953-4252.