Heat Pumps

What is an AHRI number?

An Air Conditioning, Heating, and Refrigeration Institute (AHRI) certified heat pump system confirms the efficiency ratings of specific combinations of an outdoor heat pump unit, indoor heat pump unit, and/or furnace in the case of a dual-fuel system. If any component of your heat pump system changes, the system will have a different AHRI reference number and may have different efficiency ratings. The AHRI number can be understood as a unique ID for heat pump and furnace components that were tested as one system.  The AHRI Certification Program conducts third party testing to confirm performance ratings of heat pumps, and other mechanical systems. The performance ratings for a tested heat pump system are then certified in the form of an AHRI certificate and AHRI reference number.

An AHRI reference number is required when applying for heat pump rebates available through the CleanBC Better Homes and Home Renovation Rebate Program. The AHRI reference number for your heat pump system must also be found on the Qualifying Product List. The AHRI number is used by the rebate programs to confirm and validate that you have purchased an energy efficient, and rebate eligible heat pump.  Be sure to have your contractor include the AHRI reference number for your heat pump system, including the indoor unit, outdoor unit, and/or furnace, on your invoice. Check out the sample invoices for more information on what is required on your invoice.

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What is a heat pump and what are its benefits?

A heat pump takes heat energy from one place and moves it to another – just like a refrigerator. In summer, it moves heat out of the house, and in the winter it moves heat into the house – even if it’s cold outside. Heat pumps are able to transfer heat using a process of evaporation and condensation of a substance called refrigerant that cycles between the indoor and outdoor units.

With a heat pump, you can enjoy the following benefits:

  • Year-round comfort: A heat pump takes the place of both an air conditioner and a heating system, keeping you warm in the winter and cool in the summer.
  • Maximum efficiency: When properly installed, a heat pump uses half to a third as much energy as electric baseboards or a gas furnace.
  • Climate Friendly: For an average home heated by natural gas, switching to a heat pump reduces your carbon footprint by about the same amount as not driving your car for 9 months of the year*.
  • Better indoor air quality: Most heat pumps provide air flow and dehumidification with options to add an enhanced filtration system to clean the air circulating through your home of indoor pollutants, dust, pollen, and other allergens.

*If you are using BC grid electricity, which is close to zero-emission.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

What are central ducted heat pumps?

Space heating is the largest use of energy in homes and a significant contributor to greenhouse gas emissions. A central ducted heat pump is a highly efficient, climate friendly, and modern alternative to gas or electric furnaces.

A heat pump takes heat energy from one place and moves it to another by compressing and expanding refrigerant. A heat pump extracts heat from the air and transfers this heat to either the inside or outside of your home, depending on the season. A central heat pump distributes heat and cool air through ductwork connected to vents in each room.

A diagram of a central ducted heat pump, with labels: Outside air drawn into unit, refrigerant lines, indoor unit with optional back-up heating, optional enhanced filtration, thermostat to control temperature, ductwork distributes winter heating & summer cooling

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

What are ductless mini-split and ductless multi-split heat pumps?

A ductless mini-split heat pump (also known in some cases as a ductless or mini-ducted heat pump) is the most energy-efficient and most climate friendly form of home heating and cooling currently available.

A heat pump takes heat energy from one place and moves it to another by compressing and expanding refrigerant. A heat pump extracts heat from the air and transfers this heat to either the inside or outside of your home, depending on the season. An outdoor unit connects to a wall-mounted indoor unit by a small bundle of cables, including the refrigerant line. A remote control is used to adjust settings for maximum efficiency, comfort and control.

A cross-section diagram of a ductless heat pump, with labels for: outside unit, outside air drawn into unit, refrigerant lines, indoor wall mounted head, winter heating & summer cooling, remote control to adjust temperature.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

What are air-to-water heat pumps?

Heat pumps are very efficient, and climate friendly heating systems that are used to heat the home.In Canada, air-to-water heat pumps are an alternative to the more common air-to-air heat pumps.

Unlike an air-to-air heat pump, an air-to-water heat pump does not use forced air to heat the home. Instead, this type of system uses a hydronic distribution system to heat the home with a series of radiators or in-floor heating, much like a boiler does.

They work by compressing and expanding refrigerant to transfer heat from the outside air to water, which is pumped through the system of hydronic radiators.

Air-to-water heat pumps are a good option for homeowners who want the comfort of radiant heating without the greenhouse gas emissions associated with using an oil or gas boiler.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

What is a cold climate heat pump?

Heat pumps are the perfect heating system option for colder parts of British Columbia. While in these regions, cold climate heat pumps are recommended, they become increasingly popular even in the Lower Mainland and on Vancouver Island. Cold climate heat pumps are built to work efficiently in conditions down to -25 degrees Celsius, with some systems maintaining an efficiency of over 200% at -18 degrees Celsius1.  Cold climate heat pumps have been tested in Canadian winters since the early 2010s2.
Since the air outside will always contain some heat, a heat pump can supply heat to a house even on cold winter days. In fact, air at –18°C contains about 85 percent of the heat it contained at 21°C2.

When purchasing a cold climate heat pump consult with your contractor about the right type of system for your home.   In most climate zones in the province, in particular for the lower mainland and Vancouver Island, there would be no need to install a back up heating system.  To check the average and extreme temperatures of your region see Environment Canada’s Climate Normals Data.

References

  1. Yukon Energy, Mines and Resources. An Evaluation of Air Source Heat Pump Technology in Yukon. https://www.energy.gov.yk.ca/pdf/air_source_heat_pumps_final_may2013_v04.pdf. May 31, 2013. Accessed February 2020.
  2. Natural Resources Canada. Clean Energy Fund Public Project Report. https://www.nrcan.gc.ca/sites/www.nrcan.gc.ca/files/energy/pdf/CEF-Outreach-Report.pdf. March 31, 2015. Accessed February 2020.

Do heat pumps work well in cold weather?

Heat pumps are the most energy efficient and climate friendly heating and cooling upgrade option for homes in British Columbia. A typical modern heat pump works at a high efficiency down to minus 8.3 degrees Celsius1. As the outdoor temperature decreases below this temperature the heat pump’s efficiency also decreases. Heat pumps are ideally suited for the typical climate found in British Columbia’s Lower Mainland and Vancouver Island. In areas with a colder climate, cold climate heat pumps are recommended (see our What is a Cold Climate Heat Pump FAQ).

The operational efficiency of your heat pump, and frequency that you may need to use a backup heating system, is dependent on the type and efficiency of the heat pump, your climate zone, and the design and efficiency of your home.  All heating systems work most effectively and efficiently in homes that are more energy efficient. When installing a new heating system of any type, consider what additional upgrades you can complete to make your home more efficient such as upgrading your current insulation levels or upgrading windows and doors.

Reference

  1. Natural Resources Canada. Air-Source Heat Pumps. https://www.nrcan.gc.ca/energy/publications/efficiency/heating-heat-pump/6831. Updated March 27, 2017. Accessed February 2020.

What type of heat pump should I choose?

Air-source heat pumps transfer heat that is in the outside air into the home. The most common ones transfer this heat into the indoor air, and are called air-to-air heat pumps. There are three main types of air-to-air heat pumps: central, mini-split, and multi-split.

A central heat pump distributes heat and cooling through ductwork connected to vents in each room.

A mini-split heat pump does not rely on ductwork to heat and cool the home. Instead, mini-split heat pumps use a series of one or more indoor heads located throughout the home. An outdoor unit connects to wall-mounted indoor heads by a small bundle of cables, including the refrigerant line. A remote control is used to adjust settings for maximum efficiency, comfort and control.

While the term mini-split can be used to refer to any ductless type of heat pump, it typically refers to a system that only has one indoor head. The term multi-split is often used to describe a heat pump system that has multiple indoor heads.

Not all mini-splits are completely ductless! A ducted mini-split heat pump uses short ductwork to connect a single indoor unit to multiple rooms. In these systems an indoor unit is mounted in the attic, where short ducts distribute air to multiple rooms.

The type of heat pump you choose will depend on a number of factors:

  • Size and layout of your home: Mini-split/ductless heat pumps can be used in homes of various sizes, but they are ideal for smaller homes or homes with an open plan layout.
  • State of your ducts: It’s important to check the ducts of your old heating system. Depending on their size, airtightness, and layout, a contractor may need to do some modifications and repairs prior to installing any new high efficiency heating system.
  • Interest in removing ducts: The ductless design of a mini-split heat pump makes them ideal for installation in homes that do not already have central ducted heating – for example, in homes with electric baseboards or when switching from a boiler system with radiant heating to a heat pump system. If you are interested in removing the ducting in your home to provide you with more headspace or a more efficient utilization of space, installing a mini-split/ductless heat pump will allow you to do so.
  • Zonal heat: The design of a ductless heat pump allows for zonal heating – that is, the ability to set different temperatures in different areas of your home. Zonal heating is an efficient and effective way of providing just the right amount of heat to the areas that are most commonly occupied in the home – such as common living spaces, home offices, bedrooms, and using less heat in areas that are not frequently used. Zonal heating is also useful for homes where the occupants have different heating preferences or for areas of the home that need separate heating controls – like a home with a rental suite.
  • Outdoor temperature: The heat pump you choose should be compatible with your region’s climate. Some models perform better than others in colder winter temperatures.

Other types of heat pumps

  • Air-to-water heat pumps also take heat from the outdoor air, but they transfer it into a liquid distribution (hydronic) system. Air-to water heat pumps can be used for both space heating and domestic hot water.
  • Ground-source heat pumps are another type of heat pump. The steady, moderate temperature of the ground allows these heat pumps to have high year-round efficiency. Ground-source heat pumps often do not require a backup heating system but typically have higher upfront costs than air source heat pumps. Installed cost will vary depending on your site geology and available space.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

Do I need a backup heat source for my heat pump?

Some heat pumps are designed operate independently without back up heating, while others are designed to use a back up heating system. Whether or not you need a backup heat source for your heat pump will depend on the type of heat pump you purchase, your climate zone, and the design and efficiency of your home.  In many locations of the province a back up heating system can be avoided by installing a cold climate heat pump. Visit the What is a Cold Climate Heat Pump FAQ for more information.

There are many options for a backup system. Many modern high efficiency heat pump systems come with an integrated electric resistance heating system that functions as a back-up system at low temperatures. For mini-split heat pumps installed in homes without ductwork, electric baseboards or high quality electric fireplaces are a viable back-up option. Natural gas heating systems can be used as backup systems for central heat pumps as well, but require special modifications to work as part of the same integrated home heating system. In many rural areas, wood heating is used to supplement a heat pump on the coldest days.

If you are looking to install a rebate eligible heat pump and plan to use a natural gas heating system as a back up system, special conditions apply. Please see details at Am I eligible for a heat pump rebate if it is combined with a gas, propane, or oil furnace as a back up? before you make a purchase decision.

Speak to a heat pump installer to find a system will work well in your home and meet rebate program criteria.

 

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

Are heat pumps noisy?

Both the indoor and outdoor components of a heat pump make some noise.  On average, most modern heat pump outdoor units have a sound rating around 60 decibels, equivalent to a moderate rainfall or normal conversation. Some ultra-quiet models attain lower sound level ratings. Heat pump indoor units generally have sound level ratings between 18 and 30 decibels.

Each heat pump system has a different sound level rating. This rating is specified by most manufacturers on the system’s technical specification sheet, and represents the sound, measured in decibels, generated by the heat pump when it is working at full capacity. Noise is created by the fans and compressors. The fan model and speed, as well as the airflow and pressure flow of the system, affects the level of noise that the fan will produce.

Reduce noise by looking for these features when purchasing a heat pump:

  • Variable speed fans and compressors
  • Soft start and stop functions
  • Nighttime/low sound modes
  • Insulated compressors

When having a heat pump installed, ask your contractor about the best location for the outdoor heat pump unit and how that placement may impact the noise levels of the system. Best practices call for placing the outdoor unit away from windows and adjacent buildings, and install the unit on a solid base such as a concrete pad or block with a vibration-absorbing mat to reduce noise. Using barriers like fences, landscaping or decks help disrupt the noise transmission to your home as well as your neighbours. Be sure to ask your contractor about any relevant municipal residential noise-control bylaws at different times of the day.

You can compare heat pump noise to the decibel level of common sounds using this chart:

Everyday Noises:                                                                     Sound Level Rating (dB):

Rustling Leaves 10 dB to 20 dB
Whispering 20 dB to 30 dB
Quiet Library 40 dB
Moderate Rainfall 50 dB
Refrigerator 60 dB to 70 dB
Toilet Flushing 75 dB
Heavy Traffic 80 dB

See the City of Vancouver’s “Heat Pumps & Noise: A Neighbourly Installation Guide” for additional tips and information about how installing heat pumps and minimizing noise.

Once your heat pump is installed, completing regular (annual) maintenance on your heat pump is also important to ensure your heat pump is operating well and not producing unnecessary noise.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

 

Do heat pumps provide air filtration?

Yes, both mini-split and central air source heat pumps are able to provide air filtration.

The air filtration system of the heat pump filters indoor air rather than fresh air coming in to the home and has the ability to capture airborne contaminants including dust, dirt, allergens, smoke, fibers, bacteria, viruses, fungi, and mold spores. Because the heat pump filters indoor air, it is important to minimize air leakage into the house by draftproofing the building envelope. Heat pumps can help people manage allergies by reducing airborne irritants like dust and wildfire smoke, and improve the overall air quality in the home.

Air Filtration for Central Heat Pumps

The air filtration systems for central heat pumps works the same way as it does for conventional furnaces. The air filtration component consists of an air purifier which is placed after the return vent, leading into the indoor unit (the fan evaporator coil/air handler). The three main choices for the purifiers are:

  • media air purifiers,
  • media air purifiers with photocatalytic oxidation (PCO)
  • Electronic Air Cleaners (EACs)

Air Filtration for Mini-split Heat Pumps

Mini-split heat pumps have air filters built into them. They are usually located at the top of the indoor head, covering the heat exchanger, and are easily accessible to allow for cleaning. A typical air filter will be able to filter particulates but are not able to filter volatile organic compounds such as formaldehyde from particleboard and benzene from paint.

Selecting Filters for Your Heat Pump

When selecting filters check for the Minimum Efficiency Reporting Value (MERV) or the Microparticle Performance Rating (MPR).

  • MERV rates the overall effectiveness of the air filter. A high MERV rating means a finer filter, which removes more airborne contaminants.
  • MPR is a system that ranges from MPR 300 – 1900. It rates the ability of the filter to capture airborne particles smaller than 1 micron.
  • Another common filter type is High Efficiency Particulate Air (HEPA) filter. In order to be HEPA rated, the filters must trap 99.97% of particulates 0.3 microns or larger. Some HEPA filters can trap particulates smaller than 0.3 microns. The chart below lists common particulate size.
Common Items and their respective particle sizes (in microns):
Mold Spores 10 to 30
Pollens 10 to 1000
Hair 5 to 300
Pet Dander 0.5 to 100
Typical Atmospheric Dust 0.1 to 100
Bacteria 0.3 to 60
Cooking Oil Smoke 0.03 to 1
Tobacco Smoke 0.01 to 4
Viruses 0.005 to 0.3

Maintaining Your Heat Pump’s Filter

Regular cleaning of the filters in mini-splits and replacing filters in the media air purifiers are recommended. Refer to the system’s user manual for further guidance on how and when to complete maintenance.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

What are the costs of a heat pump?

Costs for purchasing and installing a ductless or central heat pump system can vary significantly based on the size and floor plan of your home, the type, make and model of system, number of heads installed (for ductless/mini-splits), as well as design and installation considerations. Check out the rebate search tool to learn about available rebates. Be sure to get multiple quotes to compare costs, installation approach and warranties.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

What is the best way to operate my heat pump?

Heat pumps are the most efficient and climate-friendly heating and cooling systems on the market today. While heat pumps can operate up to two to three times more efficiently than conventional heating and cooling systems, your home’s long-term comfort, energy savings and operational costs are dependant on how you operate your heat pump on a day to day basis and how energy efficient your home is overall.

How Heat Pumps Work and Why You Should Operate Your Heat Pump Differently Than Other Electric or Fossil Fuel Heating Systems

Air source heat pumps use a compressor and a condenser to absorb heat from one place and release it to another. In the winter, heat pumps extracts heat from the outside air and transfer it inside to heat your home; in the summer, heat pumps work in reverse to remove heat from indoors and cool the home down. This transfer of heat requires very little electricity and allows heat pumps to operate more efficiently than conventional heating and cooling systems. Unlike conventional systems that burn natural gas, oil or propane quickly to inefficiently generate warmth, heat pumps transfer warmth gradually and require more time to reach set temperatures. Once your home has reached the desired temperature, the heat pump operates efficiently and cost effectively to sustain the temperature level. To ensure optimal performance, be mindful of how you control your heat pump. For example, if you lower your heat pump temperature too much in colder periods, your heat pump may default to its supplementary heating system, which may be less efficient and more costly over time.

Tips to Optimize the Operation of your Heat Pump

Below are the key user considerations and operational tips that will help maximize your home’s comfort and energy savings, limit the use of the supplementary heating system, as well as optimize your heat pump system’s longevity and performance.

Operation & Settings

  • Set It & Forget It: Best practice is to set your heat pump thermostat to your preferred comfortable temperature and then let it be. A heat pump is designed to maintain a steady temperature, working gradually and efficiently. Avoid large temperature set backs. If you can’t resist adjusting your thermostat, try not to lower the set point by more than 2ᵒC or so in colder weather to minimize significant fluctuations.
  • Set Your Thermostat to Your Comfort Level: Depending on the outside temperature, and the efficiency, layout, and heating distribution of your home, you may need to set your heat pump temperature higher or lower to achieve the comfort feel you want, and to help circulate warm or cool air evenly throughout your home. For example, if you typically want your home temperature to be 20ᵒC, try setting your heat pump thermostat to 21ᵒC or 22ᵒC to feel the comfort you desire.
  • Heat & Cool Mode Use: Use the ‘Heat’ or ‘Cool’ mode on the thermostat or controller rather than ‘Auto’ temperature setting to avoid unnecessary switch overs on cool summer nights or sunny winter days. As the seasons change, simply adjust your system’s controller to meet the desired temperature that feels most comfortable.

Maintenance & Care

  • Keep It Clean & Clear: To ensure optimal air flow and reduce equipment wear and tear, keep the outdoor unit grates and coils clean and clear of dripping water, snow, leaves, long grass, weeds or debris.
  • Regularly Clean Indoor Filters: Heat pumps work best when filters are clean. Replace or clean the systems filters as directed by the instruction manual, or when they become visibly dirty or the indicator light comes on. The duration between cleanings can be weeks to months depending on use.
  • Maintain It & Sustain It: Although heat pumps require minimal maintenance, as with other heating systems, follow the manufacturer recommendations for professional servicing to keep your heat pump operating at peak performance. It is important to schedule a preventative maintenance at recommended intervals, or if an issue arises.

Additional Tips for Ductless Mini-Split Heat Pump Users

  • Keep Vanes Open & Directed: Keep air vanes open to allow air flow freely throughout the unit. Direct vanes downward when heating your home, and up when cooling to circulate air best.
  • Maximize the Heating Zone: Set the temperature of the main unit slightly higher to help distribute even warmth throughout your home. If you are trying to heat or cool multiple rooms, be sure to keep doors open between the heat pump source and rooms you’d like warmed or cooled. Conversely, if you are interested in achieving more zonal conditioning, keep the doors between the source and rooms closed.

Additional Tips for Central Heat Pump Users

  • Only Use the Backup When Required: If you have a backup heating system (natural gas, propane or electric furnace, or electric baseboards), set the backup system’s thermostat 5ᵒC below your heat pump thermostat to make your heat pump the primary heating source and only use the back up as supplementary heat when needed.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

What are the maintenance requirements for heat pumps?

To ensure that your heat pump has a long service life and operates efficiently, regular maintenance is required. Homeowners can do monthly maintenance themselves for both central and mini-split heat pumps. During regular maintenance you should follow the manufacturer’s instructions.

A yearly heat pump inspection is also recommended and should be done by a competent service contractor. During the yearly inspection, the service contractor should check the refrigerant levels and make any mechanical or electrical adjustments.

For more information about maintaining your heat pump, visit Natural Resources Canada.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

What accreditations do I look for when hiring a heat pump installer?

When hiring an accredited heat pump installer, the most important accreditation they should possess is a TQ ticket (refrigeration mechanic). Also, look for the following credentials:

For air-to-air heat pump systems:

  • TECA Quality First Forced Air Guidelines Course
  • HRAI SkillTech Residential Heat Loss/Gain and Air System Design Courses
  • ASTT Registered Applied Science Technologist, Mechanical

For air-to-water heat pump systems:

  • TECA Quality First Hydronics and Combo Course
  • HRAI SkillTech Residential Heat Loss/Gain and Radiant Hydronics Design Courses
  • ASTT Registered applied Science Technologist, Mechanical

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.

How do I convert my heat pump’s capacity rating between BTUs to tons?

The size, or capacity, of the heat pump is expressed in either nominal tons or British Thermal Units (BTU). One ton of capacity is equivalent to 12,000 BTU per hour or 3.5 kW. A typical residential heat pump generally ranges between 1 to 5 tons.

In order to receive a heat pump rebate through the CleanBC Better Homes and Home Renovation Rebate Program, your heat pump invoice must indicate the heat pump’s heating capacity as either number of tons or BTUs. If this information is missing on the invoice, contact your contractor and ask them to provide you with an updated invoice with the number of tons. If the contractor listed the capacity in BTU, use the chart below to help you convert from BTU to number of tons.

BTU Number of Tons
12,000 1 Ton
18,000 1.5 Ton
24,000 2 Ton
30,000 2.5 Ton
36,000 3 Ton
48,000 4 Ton
60,000 5 Ton

Example calculation:

  • The heat pump invoice indicates 24,000 BTU.
  • 24,000 BTU ÷ 12,000 BTU/ton = 2 tons.
  • The heat pump has a 2 ton capacity.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.