Heat Pumps for Canadian Homes — Complete Guide

Is a heat pump a good choice for heating and cooling your home in Canada? 

Cynics will say that heat pumps are well and good in Florida or France but they can’t cut it in Canada.

Good news: the cynics are wrong! A properly selected heat pump can be an excellent choice to heat your home even in our cold winters!

This guide will help you confidently navigate your heat pump choices.

Table of Contents

Can a Heat Pump Really Pump Heat When the Air is Frigid?

Yes! There’s a surprising amount of heat energy in the air even on the coldest days. Air at a chilly -20°C contains just 15% less heat energy than air at a balmy 20°C.

So, there’s still plenty of heat energy to for a heat pump to collect even when it’s cold, cold, cold outdoors.

This article focuses on Air Source Heat Pumps (ASHP) — which gather heat energy from the outside air. They're the most common in Canada and have the lowest up-front cost.

Ground Source and even Water Source heat pumps are more costly to install but they're immune to outdoor temperature. They can be a great solution for our extremes of weather. Read our guide to air-source vs. ground-source vs. water-source heat pumps for Canada.

Windchill effects humans, not heat pumps. Outdoor temperatures used in heat pump specifications are always "dry bulb" temperatures — the actual temperature excluding windchill.

Seriously Though, It Gets Really Cold Where I Live

There’s no denying it — most of Canada gets pretty cold in the winter. That’s not the barrier you might think to switching to a heat pump.

Modern Cold Climate Air Source Heat Pumps (ccASHP) deliver useful heat down to -25°C or even lower.

In many parts of Canada a heat pump can deliver all the heat you need — even on the coldest days.

Canadian Heating Design Temperatures

CityProvinceHeating Design Temp.
TorontoOntario-18°C
WhitehorseYukon-36°C
YellowknifeNorthwest Territories-39°C
IqaluitNunavut-36°C
VictoriaBritish Columbia-3°C
EdmontonAlberta-31°C
ReginaSaskatchewan-32°C
QuébecQuebec-26°C
OttawaOntario-24°C
St. John'sNewfoundland and Labrador-13°C
HalifaxNova Scotia-27°C
FrederictonNew Brunswick-23°C
CharlottetownPrince Edward Island-19°C
Happy Valley-Goose BayNewfoundland and Labrador-29°C
SaskatoonSaskatchewan-32°C
LondonOntario-18°C
KitchenerOntario-15°C
HamiltonOntario-15°C
VancouverBritish Columbia-4°C
KelownaBritish Columbia-16°C
St. CatharinesOntario-13°C
SudburyOntario-28°C
Prince GeorgeBritish Columbia-28°C
CalgaryAlberta-26°C

Heat Pump Benefits — Running Costs, Safety and Environmental

So a heat pump can heat your home but what are the benefits?

  • Running costs — heat pumps are consistently cheaper than oil and propane to run. They’re even competitive with natural gas in much of the country.
  • Safety — heat pumps do away with hazards like oil leaks and carbon monoxide poisoning.
  • Planet — heating with a heat pump substantially reduces the carbon footprint of your home.

Home Heating — The Fundamentals

Understanding a few basic concepts will help you understand contractor’s proposals and make solid decisions.

  1. Heating Load — your home’s appetite for heat.
  2. Heating Capacity — the amount of heat a furnace or heat pump can deliver.
  3. Efficiency — how efficiently the appliance converts fuel or electricity into heat.
  4. System Sizing — selecting equipment to suit your home’s requirements.

Heat pumps differ from furnaces in some important ways. For heat pumps heating capacity and efficiency vary based on the outdoor temperature. Because they have to work harder when there’s less heat energy available in the air.

Heating Load

Heating load is simply a measure of the heat energy is needed to keep your home comfortably warm.

Beware rules of thumb! Some contractors will guesstimate your home's heating load. "X btus per square foot should be plenty."

Every home is different and accurately calculating the heating and cooling loads is essential to getting the right heat pump. Rules of thumb don't cut it.

Knowing a home’s Heating Load is essential to the design of an effective HVAC system — whether heat pump, furnace or boiler. 

Heating Load is can be expressed in different units: 

  • btu/h is the most common — spoken as “btu per hour” (technically british thermal units per hour but that’s a mouthful nobody bothers with).
  • kW are often used, “kilowatts”
  • mJ are sometimes used, “megajoules” (pronounced like the name Jules).

Many factors feed into the Heating Load calculation, such as:

  • Airtightness — a well sealed home has a lower heating load than a drafty home.
  • Insulation — slows heat loss and reduces heating load.
  • Floor Space and Ceiling Height — large spaces have a higher heating load.
  • Solar Gain (aka sunshine) — lots of south-facing windows will lower your heating load.
  • Outdoor temperature — as it get colder your home loses heat more quickly, increasing the heating load.
  • Indoor temperature (aka set point) — a higher setting on your thermostat means a higher heating load.
 
 HVAC science has developed mathematical models to take all these inputs and output a heating load number.
 
Our neighbours to the South use a “Manual J” calculation for heating and cooling loads. In Canada the official standard is the CSA F-280 calculation.

If you go through the Greener Homes rebate program you will need an energy advisor to prepare an Energuide report.

That report is created using a system called HOT2000 — this provides you with heating and cooling loads that are equivalent to an F-280 calculation.

Design Temperatures and Heating Load

As it gets colder outdoors your home loses heat more quickly, increasing the heating load…

Obviously climate varies by location — the coldest days in Winnipeg and Windsor are very different. To account for that, heating load is calculated based on a Design Temperature.

For heating design in Canada we use a location’s 2.5% January Design Temperature. You can look up design temperatures for all of Canada on the official map.

Iqaluit design temperature map

Design temperatures represent a location's typical "nearly coldest" temperature. Why not use the actual coldest instead temperature for designing your system instead?

Designing for our most extreme temperatures would lead to oversizing for the vast majority of the temperatures we experience. Oversizing has downsides of so it's better to accept that for a few of the very coldest hours of the year your home will be a few of degrees cooler than normal.

EnerGuide Reports Include Heating Load

Greener Homes and similar rebate programs require a home energy assessment. The Advisor who completes your assessment will calculate the heating load for your home.

When you receive your EnerGuide report take a look in the homeowner information sheet. It’s a little tucked away but you have a carefully calculated design heating load for your home right there.

design heating load 8.39 kW
Design Heating Load in an Energuide report

The Energuide report shows heating load in kW but most contractors talk in btu. The conversion is simple: kW x 3,412 = btu/h.

In this example, the design heating load of 8.39kW is equal to 28,626 btu/h (8.39 x 3,412).

The design heating load tells us that delivering about 29k btu per hour will keep the home comfortably warm when it’s about as cold as it gets outdoors. A btu is a btu, it doesn’t matter what the heat source is. Could be electric baseboards, gas furnace, oil boiler or heat pump — as long as the appliance is meeting the heating load the home will be warm.

Heating Load concepts apply no matter the heating appliance. For the rest of the concepts we’re running over things are a little more complex for heat pumps because they fluctuate with outdoor temperature…

Heating Capacity

Heating capacity is a measure of how much heat energy an appliance can deliver. This is where the behaviour of heat pumps and furnaces starts to diverge. 

The principle is simple: to keep your home comfortably warm you simply need to ensure that your heating appliance has enough capacity to meet the design heating load of your home.

Let’s take the example of a home with a design heating load of 28,000 btu/hr. As long as our appliance can deliver at least that much we are set. Practically that probably means we’d round up to an appliance with a rated capacity of 36,000 btu/hr.

In North America "tons" are the most used measure of heating capacity. 1 ton = 12,000 btu/hr. Equipment is typically produced to provide a specified numbers of tons — so a 3-ton or 36,000 btu/hr appliance will be available from many brands.

Furnace Heating Capacity

We’ll start by getting our head around furnace capacity — as they’re a bit simpler. A typical furnace is either single-stage or two-stage. Stages can be thought of as power settings. 

A single-stage furnace is either off or running full power (nothing in between). A two-stage furnace runs low, high or off.

Each stage will have a fixed heating capacity. e.g. my own gas furnace is two stage. At the lower setting it outputs 22,000 btu/h and on max setting (aka second stage) it outputs 34,000 btu/hr. In other words, my furnace has two heating capacities.

Heat Pump Heating Capacity

Like furnaces, heat pumps have a rated heating capacity. e.g. 36,000 btu/hr (aka 3 tons).

Unlike furnaces, the heating capacity of a heat pump varies with outdoor temperature. Heat pumps have to work harder to gather heat energy as the air gets colder. 

Diminishing capacity is a key factor to take into account for system design. 

Not all heat pumps are equal in how performance as outdoor temperatures fall. Some of the most advanced cold climate models can deliver their full rated capacity all the way down to -15°C. Even maintaining 75%+ of full capacity at -25°C.

If you experience a lot of hard cold days and want avoid leaning on a secodary heat source this can be a very important feature.

Efficiency

The efficiency of heat pumps also falls as the temperature does. The colder the outdoor air the harder the unit has to work to deliver heat energy.

Coefficient of Performance (CoP) is the measure of efficiency. CoP tells you how much heating (or cooling) a heat pump generates from each unit of electricity it consumes. A CoP of 1 would tell you that the heating equipment is providing one unit of heating for each unit of electricity consumed. 

In fact heat pumps have CoP values of 2, 3 or even 4 — meaning they can deliver a large amount of hea relative to the electricity they consume.

Conventional electrical heating elements have an absolute maximum CoP of 1.0. i.e. They can never do better than converting every unit of electricity into one unit of useful heat.

Heat pumps have such fantastic CoP values because they are gathering and moving existing heat energy — not generating the heat directly. It's these levels of efficiency that make heat pumps a cost effective option for heating with electricity.

Home Cooling

Any good quality heat pump should make an excellent air con for the summer months. A variable speed heat pump are particularly.excellent for summer comfort (vs. one- or two-stage options). A variable speed heat pump will run constantly at a low speed to keep your home evenly cool. 

Slow and steady cooling is optimal for dehumidifying — moving air slowly over the cooling coil removes the maximum amount of moisture.

System Sizing

There are multiple factors at play with designing a heat pump system:

  1. One appliance needs to be sized for heating and cooling.
  2. Accounting for heating capacity decreasing as the outdoor air gets colder.
  3. Coordinating with secondary heating sources, such as a gas furnace in a dual-fuel setup.

More isn't better with heat pumps! Furnaces are often oversized — meaning they have the capacity to deliver more heat than your home needs. There aren't major downsides to oversizing a furnace but substantial is a bad idea for heat pumps.

We have an article on proper heat pump sizing.

Look for a Cold Climate Heat Pump

In all but the mildest parts of Canada a cold climate heat pump is the way to go. The cold climate designation comes from Energy Star. A Cold Climate Air Source Heat Pump (ccASHP) must meet stringent requirements for capacity and efficiency at -15°C.

Natural Resources Canada keeps a list of cold climate heat pumps that are available in the Canadian market.

Cold climate heat pumps are more expensive but they have great value in colder Canadian winters. They can efficiently meet all or most heating needs in many colder parts of Canada without depending on a secondary or auxiliary heat source.

Some heat pump is better than none! If you're replacing an older central a/c unit ask your contractor about a heat pump instead. Even a less capable outdoor heat pump unit will provide excellent air con performance. It's a drop-in replacement that gives you get a second heating source and future proofing for minimal extra cost.

Using Other Heat Sources Alongside Heat Pumps

Heat pumps are commonly paired with a second heat source in Canada. Generally speaking these uses fall into two types:

  1. Dual-Fuel Systems (aka Hybrid Systems) combine a central heat pump with a conventional furnace (usually natural gas).
  2. Auxiliary Electric Heating is provided by resistance heating elements within a heat pump system.
  3. Parallel Systems leave an existing boiler or furnace system in place with mini-split heat pumps added alongside.

Benefits of Dual-Fuel Heat Pump Systems

Dual-Fuel or hybrid forced air systems are logical choice in parts of Canada. These systems combine a traditional furnace with a heat pump — with the furnace blower distributing heat from both appliances. 

A heat pump will handle heating when the weather is moderate. The furnace will take-over when the outdoor temperatures get colder. This lets you take advantage of the particular strengths of heat pumps vs. furnaces…

  1. Heat pump benefits even in coldest climates — in the coldest Canadian climates air source heat pumps won’t provide all the heating for a typical home. However you can get a lot of the benefits by running a heat pump until the weather gets too frigid and then handing off to your furnace. See more below about capacity balance point.
  2. Fuel cost savings — handing off heating duty between gas and heat pump for the lowest running cost based on fuel price and outdoor temperature. Practically this means using a thermostat system that switches over from heat pump to furnace below a certain “balance point” outdoor temperature. I expand on cost balance point below.

Heat Pump Capacity Balance Point

Capacity balance point (sometimes known simply as “balance point”) is the outdoor temperature where your heat pump can no longer keep up with heating demand.

 

Cost Balance Point

The cost of natural gas vs. electricity varies between Canadian providers. In some cases electricity is cheap so it will always be cheaper to run a heat pump than a furnace. For others it’s natural gas that’s cheap so it always works out more cost effective to run the furnace. 

Dual-fuel systems come into their own in locations where it’s sometimes but not always cheaper to run a heat pump.

Remember, heat pumps grow less efficient as outdoor temperatures fall. So the cost to run your heat pump will go up as the temperature goes down. On the other hand, a natural gas furnace has a constant efficiency no matter what the temperature.

The outdoor temperature where natural a gas furnace is cheaper to run than a heat pump, is known as the “economic balance point” (or sometimes “cost balance point”). 

 

In virtually all of Canada it's cheaper to run a heat pump than it is to heat with Oil or Propane. So dual-fuel systems are only a cost saving option if you have piped natural gas.

We’re launching a Canada-specific heating cost calculator soon. Sign up so we can keep you updated on the calculator and other fresh info!

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Auxiliary Electric Heating Benefits

There can be large benefits to going all-electric for your home — like saving the hundreds of dollars a year you pay as standing charges to the gas company no matter how little gas you use.

Using a heat pump for 100% of your heating may not be practical though. Particularly if you need to get a larger, more expensive unit to be able to handle a few very cold days in the year. In that situation it is often logical to have some low cost auxiliary heat coils added into your heat pump. 

Heat coils use the same crude but effective technology as a toaster — electricity flows through the coils and they glow red hot. Resistive heating is much more expensive to run than a heat pump. However if you’re only using aux heat for a small part of the year, to top-up your heat on the coldest days, they can be cost effective.

Benefits of Parallel Heat Pump Installs

If you have a furnace or boiler that’s going strong then parallel may be the way to go. Adding one or two mini-split units to the most used areas in your home can make a pleasant different — to your comfort and your bills.

Getting the benefit is as simple as turning down the thermostat for your existing system to save on fuel. Then use the mini-split heat pumps to keep your key rooms cosy. So you’re using highly efficient heat, exactly where you need it.

Adding mini-split or multi-split heat pumps to your home can be a great option if you have radiator or under-floor heating. The heat pumps will save money onby handling some of your heating and give you air-con for the warmer months.

Conclusion

Heat pumps can be a great solution for Canadian homes. They are a bit more complicated than a traditional furnace and a/c setup though. This article should have given you a solid foundation to continue down the path.

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