Carefully Consider a Heat Pump
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Quick Facts

Affordability

Cost Savings

CO₂ Reduction

A heat pump is an efficient form of electrically based heating and cooling. Unlike other heating and cooling systems, which convert fuel or electricity directly into heat, a heat pump moves heat from one place to another, in the same manner as an air conditioner.

Even at relatively cold temperatures, the heat pump can extract heat from outside air (air source heat pump) or from the ground or ground water (ground source heat pump) to heat your home, though efficiencies diminish as temperatures cool. During warm summer days it will function in reverse and provide space cooling.

Affordability

In general, it is not economical to use a heat pump as the only source of heat in your home. A heat pump large enough to meet heating needs would work inefficiently in summer. Combining a heat pump with an existing furnace or other supplemental heater can be a great way to reduce home energy expenses, but initial costs and additional electricity costs should be factored in.

Cost savings

In some areas of B.C., using a heat pump as part of your year-round heating and cooling system can significantly cut your heating costs. Savings will vary depending on the fuel and efficiency of your current system, and on the impact on your electricity bill. In general, heat pumps have few advantages over conventional heating systems in areas where air conditioning is not necessary, but they can be very efficient in warm to hot climates.

Health & comfort

Choosing the right kind and size of heat pump for your region and your needs can make your home temperature easy to keep comfortable all year round. Air source heat pumps aren’t likely to work effectively in areas where temperatures often go below -7°C. In northern B.C., ground source (also called earth source, geothermal or geoexchange) heat pumps can be a more effective option.

Environmental considerations

Heat pumps are much like refrigerators, which means they contain chemical refrigerants that are used to transfer heat in or out of your home. Some of these coolants contribute to depleting the ozone layer. There are models and manufacturers that use less harmful coolants. Choose a heat pump that minimizes pollution and maximizes energy efficiency.

What you need to know

General heat pump information

The efficiency of any heating system will be limited if your home has leaks or poor insulation. It often makes sense to upgrade insulation and draft proof your home before upgrading your heating system.

Do not use the cooling cycle of a heat pump when it is not essential. Use the cooling cycle to replace air conditioning not instead of other cooling practices. Passive cooling techniques, such as insulation and shading windows, are more energy-efficient ways to cool your home.

A heat pump functions by moving heat from one place to another. The outdoor coil of the heat pump absorbs heat from the outside air and transfers it to your home. In hot weather, the heat pump operates in reverse to provide cooling. It transfers heat from within your home to the outdoors.

In B.C., where heating requirements are far greater than cooling, only the heating performance should be considered when selecting a heat pump.

Air source heat pump

An Air Source Heat Pump (ASHP) functions by taking the heat from the outside air and moving it indoors rather than using a fuel to warm up the air indoors. Even at low temperatures there is enough ambient heat in the outside air to allow the heat pump to efficiently perform this transfer.

There are ASHPs that function at extremely low temperatures but for the most part they operate most effectively down to -5°C. In regions where the temperature is below -5°C for extended periods the secondary heating system will be providing the majority of the heating, thus reducing or eliminating the efficiencies gained by installing an ASHP.

The efficiency of an ASHP is directly dependant on the outside temperature. When talking to a contractor about an ASHP ensure a model is selected that is optimal for your climate region.

An ASHP, in addition to providing heating, also functions in reverse for hot times of the year by taking the hot air out of the indoor space and moving it to the outdoor space effectively cooling the indoor area. This is a much more effective and efficient method of space cooling then using an air conditioner.

In areas where heating and cooling are going to be utilized, it is important to discuss with your contractor the optimal sizing of the ASHP to ensure that efficiencies in both heating and cooling are maximized. Selecting an ASHP that provides all the heating load could potentially function poorly at a reduced cooling load, thus reducing any potential annual savings.

Ground source heat pump

A ground source heat pump (GSHP) functions very similarly to an ASHP but instead of exchanging the heat from the outside air it uses a fluid, pumped down through piping into the ground, to recover or reject the heat. The benefit of using the ground as the source for heat is that the temperature is very constant throughout the year, typically in the range of 7°C to 13°C.

GSHPs can provide very high efficiencies in optimal situations but also involve a much higher up-front cost to install piping in the ground. Installation of a GSHP is not ideal for all situations since there are many factors that must be taken into consideration, from the soil conditions, to the balancing of heating and cooling requirements (close to equal amounts of cool and heating are needed through out the year).

A qualified designer will be able to discuss this with you and make recommendations on the suitability of your location. When considering a GSHP it is important that the contractor be a trained and certified to perform the design and installation. In addition, the GSHP system should be CSA-C448 certified.

Heat pump operation

Follow these guidelines to ensure efficient, comfortable operation of heat pumps:

In the heating mode, do not set the temperature back at night or when you are out, unless you are using a "smart" programmable heat pump thermostat. Setting back a standard heat pump thermostat can increase energy consumption because it engages the supplemental heaters to bring the temperature back to the desired setpoint.
Replace filters regularly. Vacuum dirt and dust from the indoor coil once a year to prevent restricted airflow. Adequate airflow through a heat pump system is critical to ensure efficient and comfortable operation.
Keep supply vents open and free from obstruction. Closing off supply vents will restrict airflow and reduce system efficiency as well as reduce the life of the compressor.
Keep the coil in the outdoor unit clear of snow, leaves and other debris so that airflow is not restricted.
In belt-driven indoor units, check belt tension once a year and adjust if loose. The system should be adjusted annually by a trained professional.

Natural Resources Canada's Office of Energy Efficiency suggests that you select a unit with demand-defrost control to minimize defrost cycles (system reversals are hard on the machine), which in turn reduces energy needed to run the heat pump and the supplementary heat source. Have the system serviced annually by a qualified technician.

Heat pump efficiency improvements

In recent years, heat pump efficiency has increased due to the incorporation of the following improvements:

Variable speed blowers, compressors and motors provide variable speeds of operation to optimize performance and efficiency. Heat pumps with multi-speed components will typically start in the first stage or low speed. If comfort levels or settings cannot be satisfied at that speed, the second stage or high speed will activate. Some heat pump systems have more than two stages or speeds of operation.
Larger coil surface areas provide maximum heat transfer efficiency.
Time delays vary the on and off cycles of compressors, motors and, in winter, supplemental heat packages, maximizing the pump’s operating efficiency.
Expansion valves allow the heat pump to control the flow of the refrigerant more efficiently.

FAQ

I live in the south Okanagan, where the summer air temperature can reach the high 30s (°C) and the winter temperature can be -15°C on a regular basis. Am I a good candidate for a heat pump?

Yes. Heat pumps are an energy-efficient heating and cooling system and they are a great heating choice for most of southern B.C. Note, however, that in areas where summer temperatures do not warrant air conditioning, using a heat pump is far less efficient than using passive cooling techniques, such as increasing attic insulation and shading windows.

In areas like the south Okanagan and other parts of the southern Interior, cooling with heat pumps instead of air conditioners is an energy-efficient choice. In more temperate summer climates, combine passive techniques with a ceiling fan when necessary and save your heat pump use for winter. This will reduce your energy use and your energy bills.

I have heard that some heat pumps can be noisy. Is this true? How can I ensure the model I get is quiet?

Natural Resources of Canada's Office of Energy Efficiency has some information on the sound rating of heat pumps: sound rating is a tone-corrected, A-weighted sound power level, expressed in bels. Select a heat pump with an outdoor sound rating in the vicinity of 7.6 bels or lower if possible. The sound rating is an indicator of the sound power level of the heat pump outdoor unit. The lower the value, the lower the sound power emitted by the outdoor unit. These ratings are available from the manufacturer, and are published by the Air-Conditioning and Refrigeration Institute (ARI), 4301 North Fairfax Drive, Arlington, Virginia 22203, U.S.A.

Our heating system is fine right now, but we are looking to get air conditioning for the summer. Would a heat pump be a good way to go?

It would be very inefficient – and expensive – to have a heat pump installed to use only as an air conditioner. Most parts of B.C. don’t require the use of summer air conditioning on very many days in a year, and even in the hot parts of Southern B.C., a heat pump is not a good investment solely for air conditioning.

However, for year-round comfort and efficiency, you can augment your whole home heating and cooling system with a heat pump, keeping your existing furnace intact to use as supplementary heater.