However, warranties vary between manufacturers, so be sure to check the fine print. The expansion device lowers the pressure created by the compressor. No need for an outdoor thermostat control on add-on heat pumps. The lifespan of the ground loop itself approaches 75 years. A heat pump is an electrically driven device that extracts heat from a low temperature place (a source), and delivers it to a higher temperature place (a sink). For those accustomed to thermostat setback and programmable thermostats, this may be a worthwhile investment. At 8C, COPs can range from 1.1 to 3.7. A number of publications explaining how to do this are available from Natural Resources Canada. Ground-source systems will reduce your heating and cooling costs substantially. Because of this, air-air heat pumps generally try to optimize their efficiency by providing a higher volume of warm air, and heating that air to a lower temperature (normally between 25 and 45C). On a seasonal basis, the heating seasonal performance factor (HSPF) of market available units can vary from 7.1 to 13.2 (Region V). The liquid refrigerant absorbs heat from the outdoor air and boils, becoming a low-temperature vapour. Demand-frost controls monitor airflow, refrigerant pressure, air or coil temperature and pressure differential across the outdoor coil to detect frost accumulation. Here are some common terms you may come across while investigating heat pumps. Programmable control to allow for user selection of automatic heat pump or fan-only operation, by time of day and day of the week. Depending on the size of your new heat pump, some modifications may be needed to your ductwork to avoid added noise and fan energy use. Actual savings are highly dependant on the location of your heat pump installation. Other features available with some of these electronic thermostats include the following: Savings from programmable thermostats are highly dependant on the type and sizing of your heat pump system. It is determined by dividing the cooling capacity of the heat pump in Btu/h by the electrical energy input in Watts (W) at a specific temperature. Horizontal loop installations use trenches anywhere from 150 to 600 mm (6 to 24 in.) This section presents the basics of how a heat pump works, and introduces different system types. Actual energy savings will vary depending on the local climate, the efficiency of the existing heating system, the costs of fuel and electricity, the size of the heat pump installed, borefield configuration and the seasonal energy balance, and the heat pump efficiency performance at CSA rating conditions. Air-water heat pumps operate more efficiently when heating the water to lower temperatures, i.e., below 45 to 50C, and as such are a better match for radiant floors or fan coil systems. This liquid returns to the expansion device, and the cycle is repeated. Consult a local heat pump contractor to design, install and service your equipment to ensure efficient and reliable operation. The energy savings from installing a heat pump can help to reduce your monthly energy bills. If you are looking to implement a heat pump to replace or supplement your central furnace, you should be aware that heat pumps generally operate at higher airflows than furnace systems. Energy Efficiency Ratio (EER): The EER is similar to the COP, and describes the steady-state cooling efficiency of a heat pump. Your contractor will be able to give you guidance on your specific case. Split systems allow the coil to be added to a forced-air furnace, and use the existing blower and furnace. Indoor air is heated by the heat pump. Typically, units operating at the minimum prescribed SEER and HSPF are characterized by single speed heat pumps. Using these questions as a guide, this booklet describes the most common types of heat pumps, and discusses the factors involved in choosing, installing, operating, and maintaining a heat pump. On average, a well designed ground-source system will yield savings that are about 10-20% more than would be provided by a best in class, cold climate air-source heat pump sized to cover most of the building heating load. The size of the heat pump unit and the manufacturer's specifications will determine the amount of water that is needed for an open system. The ground water is pumped to a heat exchanger, where thermal energy is extracted and used as a source for the heat pump. Just like a steeper hill requires more effort to climb on a bike, greater temperature differences between the source and sink of the heat pump require it to work harder, and can reduce efficiency. In fact, it is likely that you interact with heat pump technology on a daily basis: refrigerators and air conditioners operate using the same principles and technology. Heat pumps can be an excellent choice in a variety of applications, and for both new homes and retrofits of existing heating and cooling systems. In addition to these regulations, your province or territory may have more stringent requirements. The Region 5 HSPF is most reflective of heat pump performance in the Ottawa region. Regardless of the approach used, the system should be designed to prevent any environmental damage. Steady state metrics include: Coefficient of Performance (COP): The COP is a ratio between the rate at which the heat pump transfers thermal energy (in kW), and the amount of electrical power required to do the pumping (in kW). First, the reversing valve switches the device to the cooling mode. Lower-end systems typically employ two stage compressors, relatively standard size refrigerant-to-air heat exchangers, and oversized enhanced-surface refrigerant-to-water heat exchangers. In heating mode, the heat pump provides thermal energy to the hydronic system. Your contractor or equipment manufacturer can tell you what level of water quality is acceptable and under what circumstances special heat-exchanger materials may be required. It looks and operates in the same manner as the outdoor portion of an air-conditioner. Copper tubing is used in the case of DX systems. To understand this process, think about a bicycle ride over a hill: No effort is required to go from the top of the hill to the bottom, as the bike and rider will move naturally from a high place to a lower one. Weather data characteristics of long-term climate conditions are used to represent the heating season in calculating the HSPF. They allow for a significant reduction in our energy consumption. If a heat pump is undersized, you will notice that the supplemental heating system will be used more frequently. You should have a qualified contractor do annual maintenance on your unit to ensure everything is in good working order. Find an explanation of single speed and variable speed heat pumps in the Air-Source Heat Pump section. This will reduce the savings that you might have expected to achieve by installing the heat pump. Below this temperature, a supplemental system must be used to provide heating to the building. Also, be sure that vents and air registers in your home are not blocked by furniture or carpeting, as inadequate airflow to or from your unit can shorten equipment lifespans and reduce efficiency of the system. Apart from sizing, several additional performance factors should be considered: Air-source heat pumps should be installed by a qualified contractor. In Canada, energy efficiency regulations prescribe a minimum seasonal efficiency in heating and cooling that must be achieved for the product to be sold in the Canadian market. To reduce energy consumption and greenhouse gas emissions, we must rethink traditional methods of heating and cooling. The ground water exiting the heat exchanger is then reinjected into the aquifer. Stage one calls for heat from the heat pump if the temperature falls below the pre-set level. A variety of sizes of systems are available to suit the Canadian climate. To this end, a compressor inside the device uses electricity to increase the temperature of the heat extracted from the outside air. The pipe is placed in one of three types of arrangements: Regardless of the arrangement you choose, all piping for antifreeze solution systems must be at least series 100 polyethylene or polybutylene with thermally fused joints (as opposed to barbed fittings, clamps or glued joints), to ensure leak-free connections for the life of the piping. To support understanding of this section, refer to the earlier section called An introduction to Heat Pump Efficiency for an explanation of what HSPFs and SEERs represent. If transitioning from a natural gas or fuel oil based heating system, it may be necessary to upgrade your electrical panel. Unlike conventional thermostats, these thermostats achieve savings from temperature setback during unoccupied periods, or overnight. Air-Water Heat Pumps: Less common in Canada, air-water heat pumps heat or cool water, and are used in homes with hydronic (water-based) distribution systems such as low temperature radiators, radiant floors, or fan coil units. Finally, the reversing valve sends the gas, which is now hot, to the indoor coil, which is the condenser. Most air-source systems shut off at one of three temperatures, which can be set by your installation contractor: Most supplementary systems can be classed into two categories: An outdoor temperature sensor shuts the heat pump off when the temperature falls below the pre-set limit. The indoor coil is where heat is transferred to/from indoor air in certain types of air-source heat pumps. NRCans ASHP-Eval tool is freely available and could be used by installers and mechanical designers to help advise on your situation. In thinking of the home as a system, it is recommended that heat losses from your home be minimized from areas such as air leakage (through cracks, holes), poorly insulated walls, ceilings, windows and doors. This type of system can meet all cooling loads and most heating loads on low speed, with high speed required only for high heating loads. Heat pumps are a proven and reliable technology in Canada, capable of providing year-round comfort control for your home by supplying heat in the winter, cooling in the summer, and in some cases, heating hot water for your home. This section explores how air-source heat pumps can benefit your household energy footprint. In the heating cycle, the ground water, the antifreeze mixture or the refrigerant (which has circulated through the underground piping system and picked up heat from the soil) is brought back to the heat pump unit inside the house. The heat is then pumped outside, into a water body or return well (in an open system) or into the underground piping (in a closed-loop system). The compressor is the critical component of the system. By running a heat pump, you will use less gas or oil, but more electricity. Since air-source heat pumps have a minimum outdoor operating temperature (between -15C to -25C) and reduced heating capacity at very cold temperatures, it is important to consider a supplemental heating source for air-source heat pump operations. Heating and cooling loads should be determined by using a recognized sizing method such as CSA F280-12, "Determining the Required Capacity of Residential Space Heating and Cooling Appliances.". Unlike air-source heat pumps, where one heat exchanger is located outside, in ground-source systems, the heat pump unit is located inside the home. This water can then be used to serve terminal systems like radiators, a radiant floor, or fan coil units via a hydronic system. Improved temperature control, as compared to conventional thermostats. Range, SEER in Market Available Products: 14 to 42, Minimum HSPF (Canada): 7.1 (for Region V), Range, HSPF in Market Available Products: 7.1 to 13.2 (for Region V), Range, Heating COP in Market Available Products: 3.8 to 5.0, Range, EER in Market Available Products: 19.1 to 27.5, Range, Heating COP in Market Available Products: 3.2 to 4.2, Range, EER in Market Available Products: 14.6 to 20.4. A heat pump extracts heat from the cold outside air and transfers it inside our home. Ground-source heat pumps use the earth or ground water as a source of thermal energy in heating mode, and as a sink to reject energy when in cooling mode. If you have an extra existing well, your heat pump contractor should have a well driller ensure that it is suitable for use as a rejection well. Most ground-source heat pump units are covered by a one-year warranty on parts and labour, and some manufacturers offer extended warranty programs. Ground-source heat pumps are designed in different ways. However, going up the hill requires a lot more work, as the bike is moving against the natural direction of motion. Will I need to make additional modifications to my home? Selecting the source and sink for your heat pump system goes a long way in determining the performance, capital costs and operating costs of your system. There are two types of outdoor thermostats used with these systems. As this temperature drops, the ability of the heat pump to absorb heat also drops. It is therefore important to have a good understanding of your heating load and what the heat pump operating characteristics are to achieve optimal energy savings. A performance standard specifies tests and test conditions at which heat pump heating and cooling capacities and efficiency are determined. This section provides a brief overview of common sources and sinks for residential applications in Canada. wide. A heat pump uses additional electrical energy to counter the natural flow of heat, and pump the energy available in a colder place to a warmer one. Neither vertical nor horizontal loops have an adverse impact on the landscape as long as the vertical boreholes and trenches are properly backfilled and tamped (packed down firmly). That is why our researchers are hard at work trying to adapt air-source heat pumps to our Canadian climate. The operating costs of a ground-source system are usually considerably lower than those of other heating systems, because of the savings in fuel. You should also ensure that your air vents and registers are not blocked by any furniture, carpeting or other items that would impede airflow. Many online calculators are available to provide a quick estimation of how much energy savings you can expect for your particular application. The condenser is a coil in which the refrigerant gives off heat to its surroundings and becomes a liquid. As a result, a ground-source heat pump can provide more heat over the course of the winter than an air-source heat pump. They can be further classified according to the type of installation: Air-air systems are more efficient when the temperature difference between inside and outside is smaller. Today, air-source heat pumps represent one of the most promising technologies for heating and cooling our homes. If you are switching to a heat pump from a furnace, you may notice this when you begin using your new heat pump. To help with this process, NRCan has developed an Air-Source Heat Pump Sizing and Selection Guide. It is generally a large compartment immediately above or around the heat exchanger. Check with local authorities to determine if restrictions apply in your area. The latter is particularly important for vertical heat-exchanger systems. The outdoor unit is where heat is transferred to/from the outdoor air in an air-source heat pump. More recently, air-source heat pumps that are better adapted to operating in the cold Canadian climate have been introduced to the market. Vertical loops require little space and result in less lawn damage. The electricity input into the heat pump is used to transfer thermal energy between two locations. As with air-source heat pumps, ground-source heat pump systems are available in a range of different efficiencies. The performance testing standards for air-source heat pumps are CSA C656, which (as of 2014) has been harmonised with ANSI/AHRI 210/240-2008, Performance Rating of Unitary Air-Conditioning & Air-Source Heat Pump Equipment. This leaves bare areas that can be restored with grass seed or sod. Payback period is dependent on a variety of factors such as soil conditions, heating and cooling loads, the complexity of HVAC retrofits, local utility rates, and the heating fuel source being replaced. For hydronic systems, both the source and sink heat exchangers and compressor are in a single cabinet. As the refrigerant passes from the reversing valve to the compressor, the accumulator collects any excess liquid that did not vaporize into a gas. The heat pump simply removes or adds heat to the water; no pollutants are added. Sources: Two sources of thermal energy are most commonly used for heating homes with heat pumps in Canada: Sinks: Two sinks for thermal energy are most commonly used for heating homes with heat pumps in Canada: Furnaces and boilers provide space heating by adding heat to the air through the combustion of a fuel such as natural gas or heating oil. Plastic piping must be thermally fused, and there must be good earth-to-pipe contact to ensure good heat transfer, such as that achieved by Tremie-grouting of boreholes. Moisture in the air passing over the indoor coil condenses on the coil's surface and is collected in a pan at the bottom of the coil. The sizing of your heat pump system should be done according to your climate, heating and cooling building loads, and the objectives of your installation (e.g., maximizing heating energy savings vs. displacing an existing system during certain periods of the year). While an open system drains water from a well, a closed-loop system recirculates the antifreeze solution in the pressurized pipe. Canadas cold climate is a challenge: when the temperature drops, heat pumps have trouble transferring heat from outdoors to indoors in order to warm our homes. This process is reversed in cooling mode, and thermal energy is extracted from the hydronic system and rejected to the outdoor air. The incremental cost of such a system can be recovered through energy cost savings over a period as low as 5 years. The reversing valve directs the refrigerant vapour to the compressor. For cost-effectiveness, the system should generally be sized to cover the majority of the households annual heating energy requirement. This can be done through: A ductless indoor unit, such as a wall mounted unit. The cost of installing an air-source heat pump depends on the type of system, your design objectives, and any existing heating equipment and ductwork in your home. The heat is transferred to the refrigerant, which boils to become a low-temperature vapour. As such, it is very important to examine the supply airflow of your system, and how it may compare to the airflow capacity of your existing ducts. While the supplemental heating system operates less frequently, under warmer ambient conditions, the heat pump produces too much heat and the unit cycles on and off leading to discomfort, wear on the heat pump, and stand-by electric power draw. Depending upon the amount of the setback and temperature drop, the heat pump may not be able to supply all of the heat required to bring the temperature back up to the desired level on short notice. The antifreeze solution must be acceptable to local environmental officials. The refrigerant picks up heat from the house air and transfers it directly, in DX systems, or to the ground water or antifreeze mixture. The active cooling cycle is basically the reverse of the heating cycle. It is important that horizontal and vertical loops be installed by a qualified contractor. The minimum efficiency for each type is regulated at the federal level as well as in some provincial jurisdictions. Consult a local heating and cooling professional to size, install, and maintain your equipment to ensure efficient and reliable operations. The most common type of thermostat used is the "set and forget" type. Region 5 would cover most of the southern half of the provinces in Canada, from the B.C interior through New BrunswickFootnote 1. The cycle described above is reversed to cool the house during the summer. The heat pump can also provide cooling by transferring warm indoor air to the outside. You should also have your water tested for acidity, hardness and iron content before installing a heat pump. A condensate drain connects this pan to the house drain. The ability of the heat pump to transfer heat from the outside air to the house depends on the outdoor temperature. In an open system, the ground water is then pumped back out and discharged into a pond or down a well. This causes the temperature to drop, and the refrigerant becomes a low-temperature vapour/liquid mixture. It is recommended that a heating and cooling professional be retained to undertake the required calculations. As a result, the demand-frost method is generally more efficient since it starts the defrost cycle only when it is required. Installation of an open system is often subject to local zoning laws or licensing requirements. It is important to note that these HSPF estimates are for an area with a climate similar to Ottawa. Stage two calls for heat from the supplementary heating system if the indoor temperature continues to fall below the desired temperature. The Canadian Standards Association (CSA) currently verifies all heat pumps for electrical safety. So how does a heat pump heat or cool your home? more thermal energy is produced than the amount of electric energy used to pump it. Actual savings in your house will depend on a number of factors, including your local climate, efficiency of your current system, size and type of heat pump, and the control strategy. The Heating Cycle: Providing thermal energy to the building, The Cooling Cycle: Removing thermal energy from the building. The higher efficiency of the heat pump can translate into significant energy use reductions. Improper installation may result in poorer heat pump performance. Programmable heat pump thermostats are available today from most heat pump manufacturers and their representatives. A heat pump of 10-kW (34 000-Btu/h) capacity will use 0.45 to 0.75 L/s while operating. Most ducted residential single-speed heat pump systems are installed with a "two-stage heat/one-stage cool" indoor thermostat. Tackling these issues first can allow you to use a smaller heat pump size, thereby reducing heat pump equipment costs and allowing your system to operate more efficiently. Because of this, most air-source installations require a supplementary heating source to maintain indoor temperatures during the coldest days. This sends hot gas to the outdoor coil to melt the frost. The performance testing standards for ground-source systems are CSA C13256 (for secondary loop systems) and CSA C748 (for DX systems). Air-source heat pumps have a service life of between 15 and 20 years. The unit takes heat out of the indoor air and rejects it outside. This unit generally contains a heat exchanger coil, the compressor, and the expansion valve. Heat pumps are one of the many technologies that CanmetENERGY believes will help make Canada a safer, healthier place, and create a low-carbon economy. The amount of frost buildup depends on the outdoor temperature and the amount of moisture in the air. In some regions and cases, this added cost can be recouped in a relatively short time period through the utility cost savings. Ranges of COPs and EERs for market available units are provided below. Air-source heat pumps have a minimum outdoor operating temperature, and may lose some of their ability to heat at very cold temperatures. The compressor squeezes the molecules of the refrigerant gas together, increasing the temperature of the refrigerant. The plenum , only seen in ducted installations, is part of the air distribution network. Ground-source systems continue to operate regardless of the outdoor temperature, and as such are not subject to the same sort of operating restrictions. There, you can find discussion of options for how to program your system to transition between heat pump use and supplementary heat source use. Heat pump systems generally supply a greater volume of airflow at lower temperature compared to furnace systems. The direction of the refrigerant flow is changed by the reversing valve. Heat pumps operate on a different principle. The actual SEER or HSPF values depend on a variety of factors primarily related to heat pump design. All installations should meet the requirements of CSA C448 Series 16, an installation standard set by the Canadian Standards Association. Heat pumps in general come at a higher cost compared to other systems such as furnaces or electric baseboards due the number of components in the system. However, the age of the service and the total electrical load of the house may make it necessary to upgrade. The total installed cost of ground-source systems varies according to site-specific conditions. The vapour is then compressed, reducing its volume and causing it to heat up. Ground heat exchanger designs can be classified as either: The selection of outdoor piping system depends on the climate, soil conditions, available land, local installation costs at the site as well as municipal and provincial regulations. Heres the situation: Nearly two thirds of the energy consumed in Canadian homes is used for heating and cooling. You should not use water from a spring, pond, river or lake as a source for your heat pump system. Once this is done, you can forget about the thermostat; it will automatically switch the system from heating to cooling mode or vice versa. Although this is accomplished in different ways by different manufacturers, the heat pump brings the house back to the desired temperature level with or without minimal supplementary heating. Variable speed air-source heat pumps are now available that are designed to vary the capacity of the system to more closely match the heating/cooling demand of the house at a given moment. How much servicing will the system require? In a closed-loop system, the antifreeze mixture or refrigerant is pumped back out to the underground piping system to be heated again. The vapour is then compressed, reducing its volume and causing it to heat up. This allows the heat pump to operate more efficiently, with typical efficiencies well over 100%, i.e. Generally, the indoor unit contains a heat exchanger coil, and may also include an additional fan to circulate heated or cooled air to the occupied space.