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Concerned about rising energy costs? Want a high efficiency heating and cooling solution at a reasonable cost?

SAY HELLO to the Hydron-Aire EVi Air to Water Heat Pump

The Hydron-Aire EVi Air to Water Heat Pump uses innovative hydronic technology to supply energy to your home including:

• both heating and cooling, no need for a separate air conditioning unit

• radiant floor heating and cooling

• domestic hot water


Heat pumps are a proven technology

Heat pumps are a proven technology that has been used for decades, both in Canada and globally, to efficiently provide heating, cooling and hot water to buildings. (Put this text in a box with same blue colour background as the EVi Advantages)

EVi Air to Water Heat Pumps are the most efficient air source solution on the market today – approximately 3 to 4 times greater thermal efficiency than natural gas. Additionally, EVi’s record-breaking low operating ambient temperature range (down to -30 degrees C) means less reliance on all electric and gas back-up sources.

PLUS, Wi-Fi enabled controls and thermostats allow you to monitor and adjust the system from anywhere.


Hydron-Aire EVi Air to Water Heat Pumps are the solution to:

• RISING ENERGY COSTS: EVi captures energy from air saving up to 40% when compared with traditional heating/cooling systems

• RELIANCE ON FOSSIL FUELS: EVi eliminates the need for fossil fuels

• UNSTABLE TEMPERATURES: with variable speed technology EVi heat pumps run at more consistent intervals eliminating uneven temperatures throughout the space while also providing increased air filtration.


GOVERNMENT INCENTIVES: Check with your local provincial and municipal government as well as energy providers to see what incentives may be available in your area. We cover provincial rebates in our news section as well!

ELECTRIC BACKUP AVAILABLE: You can choose to have an electric form of backup heat depending on what type of system you have. For example, our thermal storage tank comes with 12kw of backup heating elements to keep the water hot in case the heat pump stops operating. If you have an air handling unit for air distribution, you may also add in an electric backup heater to keep the air hot.

QUIET OPERATION: The outdoor heat pump can range from approximately 43dB to 48dB depending on the size of the heat pump.

DEFROST CYCLE: A defrost cycle removes the frost from the outdoor coil. Frost conditions will occur when the coil temperature is lower than the dew point of the outdoor ambient air. The defrost cycle should be long enough to melt the ice, but short enough to be energy efficient. The defrost cycle on our heat pumps lasts only a few minutes because we can use the stored heat of the water in the storage tank to accelerate the process. Because of using this stored energy, the system efficiency is improved compared to traditional outdoor heat pumps.

PROUDLY TÜV RHEINLAND CERTIFIED: We are certified by TÜV Rheinland, which stands for safety and quality in virtually all areas of business and life. Founded almost 150 years ago, the company is one of the world’s leading testing service providers.

5-YEAR WARRANTY: Our heat pump comes with a 5-year parts warranty.

How air to water heat pump systems Work?

An air to water heat pump is a piece of mechanical equipment that extracts thermal energy from the air and uses it to heat or cool water.

An air-source heat pump system works by concentrating and transferring thermal energy between the outside air and indoor space. For example, when providing heat to the indoor space, a fan draws air through the heat pump’s evaporator, which is situated in the outdoor heat pump. The thermal energy in the air is transferred to a refrigerant which changes its physical state and evaporates even at low temperatures, absorbing the energy. The heat pumps compressor increases the pressure of that refrigerant and then feeds this now energy-dense refrigerant into the heat pumps condenser which transfers the thermal energy into a water and glycol mixture. This hot fluid is pumped through pipes into the indoor space and used to heat radiant floors, warm air and or heat domestic water.

ENhanced vapor injection technology

Enhanced Vapor Injection is a technology used on our cold climate heat pumps to achieve higher performance at lower temperatures. An EVI heat pump uses a 3rd smaller internal plate heat exchanger called an “Economizer” within the refrigeration cycle to provide optimal refrigerant pressures and temperatures to a twin inlet compressor. These features allow the heat pump to efficiently and reliably extract energy from much colder air than standard heat pumps.
With the right control system, multiple comfort zones can be serviced within a home or building.
Heat pumps are a proven environmentally friendly technology that saves energy and money. However traditional air to air and air to water heat pumps cannot efficiently extract energy from winter air conditions. When you need the most heat they give you the least and at their worst efficiency. That’s where Hydron-Aire EVI steps in!
EVI technology allows our heat pumps to maintain high efficiency and capacity down to -30C air temperatures.
In addition, an air to water heat pump can be used to heat domestic water. A dedicated heat exchanger or hot water tank with a built-in heat exchanger is used to transfer heat from the heat pump system to heat domestic hot water. We even offer specific models for pools and hot tubs.

The EVI technology allows our heat pumps to operate efficiently down to much lower outdoor temperatures than standard heat pumps.

The EVI technology allows our heat pumps to operate efficiently down to much lower outdoor temperatures than standard heat pumps. To do this it utilizes a refrigeration compressor with two suction inlets instead of one. In low temperatures, a portion of refrigerant gas is reinjected into the second compressor connection to lower the total pressure difference the compressor must work against. The compressor is then sped up to do the same total work thus maintaining heating capacity.

To illustrate we can compare a heat pump to a vehicle. For example, a truck may be used to pull a load of material up a hill. The heavier load you want to move up the hill the more powerful engine you need. But the more powerful engine will take more energy to operate even when the extra power is not needed. Ideally, when the hill is steep, you simply reduce the amount you pull but make more trips to get the job done. Then you can drive a truck with a smaller and more efficient engine year-round, saving you money.

A heat pump does the same thing by moving heat energy from a low-temperature location to a higher temperature location. The heat pump compressor has to be sized to operate efficiently during low load conditions. But when the difference between the outdoor and indoor temperature is high, traditional heat pump compressors will have insufficient power to get the job done. EVI technology allows the compressor to pull less energy up the hill per cycle and work faster, thus maintaining heat output.


Our EVI heat pumps continually monitor the compressors operating conditions and varies the speed and refrigerant flow through electronic expansion valves to keep it in its safe operating window. In extreme conditions, the heat pump artificially increases the cooling sent to the compressor’s electric motor using a refrigerant-to-refrigerant heat exchanger. These strategies and components have been used for decades in our large commercial variable speed equipment and are proven reliable solutions.

Efficiency at very low temperatures

These graphs illustrate the heat pump running at a cold temperate and the efficiency it achieves

Efficiency of pump at temperatures below -20C
Efficiency of pump at temperatures below -20C