Heat Pumps 101: 8 of The Most Common Questions About Heat Pumps Explained

Heat pumps are an efficient, effective way to heat Nova Scotia homes, and getting one might be easier than you think.

Heat pumps are a great way to save money, stay comfortable all year and breathe cleaner air throughout your home or office. As a Nova Scotia Power Preferred Contractor we are able to offer financing through the Nova Scotia Power heat pump financing program as well as through other avenues such as Credit Union Atlantic and Sandpiper.

As a primary heating system or as a compliment to electric, gas or oil heat, contact us today to see how a heat pump can increase your comfort and save you money on your heating your home.

Heat pumps also provide customized temperature control for air conditioning and dehumidification. From zoning to air purification we have the solution that will suit your home and budget.

However, heat pumps can be confusing if you don't understand the benefits of owning one! Let us break it down for you below.

What is a heat pump?

A heat pump is a versatile, efficient cooling and heating system. Thanks to a reversing valve, a heat pump can change the flow of refrigerant and either heat or cool a home. Air is blown over an evaporator coil, transferring heat energy from the air to the refrigerant. Heat pumps are much more efficient than traditional heating methods - twice as efficient as traditional oil systems - and they provide the added benefit of air conditioning.

To the right is a sample of a Daikin 19 Series ducted heat pump. The top piece is the interior system, and the bottom is the exterior.

How does a heat pump work?

One of the most important things to understand about heat pump operation and the process of transferring heat is that heat energy naturally wants to move to areas with lower temperatures and less pressure. Heat pumps rely on this physical property, putting heat in contact with cooler, lower pressure environments so that the heat can naturally transfer. This is how a heat pump works.

COOLING MODE

STEP 1

Liquid refrigerant is pumped through an expansion device at the indoor coil, which is functioning as the evaporator. Air from inside the house is blown across the coils, where heat energy is absorbed by the refrigerant. The resulting cool air is blown throughout the home’s ducts. The process of absorbing the heat energy has caused the liquid refrigerant to heat up and evaporate into gas form.

STEP 2

The gaseous refrigerant now passes through a compressor, which pressurizes the gas. The process of pressurizing the gas causes it to heat up (a physical property of compressed gases). The hot, pressurized refrigerant moves through the system to the coil in the outdoor unit.

STEP 3

A fan in the outdoor unit moves outside air across the coils, which are serving as condenser coils in cooling mode. Because the air outside the home is cooler than the hot compressed gas refrigerant in the coil, heat is transferred from the refrigerant to the outside air. During this process, the refrigerant condenses back to a liquid state as it cools. The warm liquid refrigerant is pumped through the system to the expansion valve at the indoor units.

STEP 4

The expansion valve reduces the pressure of the warm liquid refrigerant, which cools it significantly. At this point, the refrigerant is in a cool, liquid state and ready to be pumped back to the evaporator coil in the indoor unit to begin the cycle again.

HEATING MODE

A Heat pump in heating mode operates just like cooling mode, except that the flow of refrigerant is reversed by the aptly named reversing valve. The flow reversal means that the heating source becomes the outside air (even when outdoor temperatures are low) and the heat energy is released inside the home. The outside coil now has the function of an evaporator, and the indoor coil now has the role of the condenser.

The physics of the process are the same. Heat energy is absorbed in the outdoor unit by cool liquid refrigerant, turning it into cold gas. Pressure is then applied to the cold gas, turning it to hot gas. The hot gas is cooled in the indoor unit by passing air, heating the air and condensing the the gas to warm liquid. The warm liquid is relieved of pressure as it enters the outdoor unit, turning it to cool liquid and renewing the cycle.

What is the benefit of having a heat pump?

A heat pump only uses electricity for power rather than for the generation of heat, therefore, it offers a remarkably high efficiency rate. When using traditional resistive electric heat – such as electric baseboard or space heaters, for instance – the amount of heat generated is proportional to the amount of electricity used: one unit of heat per unit of electricity for 100% efficiency- meaning overall lower electricity costs to make your home comfortable.

Save money and energy: Heat pumps are twice as efficient compared to traditional oil heating systems. Plus, we can help you find rebates available through our network of contractors.

Stay cool in the summer: Heat pumps also provide air conditioning in the summer and can work to dehumidify your home on muggy days, which traditional heating systems cannot do.

On-bill financing: We can help you invest in the benefits of a heat pump through our easy, on-bill financing options.

Clean: Heat pumps clean the air in your home, they also help eliminate fuel storage and combustion on your property.

Easy installation: Installation is a breeze. Our network of qualified contractors will help you through each step of purchasing your heat pump, all the way through to the install. You also have the added benefit of no more fuel deliveries or fear of running out of oil.

How does a heat pump affect heating and electricity bills?

The energy savings from installing a heat pump can help to reduce your monthly energy bills. Achieving a reduction in your energy bills greatly depends on the price of electricity in relation to other fuels such as natural gas or heating oil, and, in retrofit applications, what type of system is being replaced.

Heating makes up half the energy bill in most Nova Scotian homes, making it the single largest use of energy for most of us. Upgrade to an efficient home heating system and you can get rebates to complement your monthly savings and comfortable home. Efficient heating systems like heat pumps, wood/pellet stoves, water heaters, and solar can save you money, by using less energy.

Can heat pumps withstand Nova Scotian winters?

Heat pumps extract or reject heat from the outside air, even in cold weather. They use an electrically powered compressor and are extremely effective at heating and cooling an apartment or a house. Daikin heat pumps are quiet and discreet and use state-of-the-art technology to keep your warm in the winter, and cool in the summer.

HOWEVER, it is important to maintain your exterior unit during the cold winter months by checking for snow or ice build-up during the winter to ensure good air flow through the unit. If snow or ice restricts the air flow, you will lose efficiency and your heat pump will strain to keep up its pace.

Can I heat my home with heat pumps without any other heat source?

In certain warmer climates, heat pumps can be the sole source of winter heat. However, here in Nova Scotia, we recommend that most homes have either a primary or backup source of heat for very cold days or long periods of low temperatures during which heat pumps would have trouble recovering from heat loss. These other sources can be oil, natural gas, propane, or electric. See our More for Your Home section for more information on other heating sources.

How long do heat pumps last?

The lifespan of a heat pump is generally 15 to 20 years, depending on how well it is maintained. Be sure to ask about warranty coverage when choosing a heat pump dealer. Daikin Atlantic dealers offer a 10-year limited labour guarantee, and up to 12-year limited parts guarantee for ultimate peace of mind for homeowners investing in their family’s comfort.

Heat pumps are a great heating and cooling solution for the Atlantic Canadian climate. Click for more information on our maintenance packages to ensure your heat pumps lasts as long as it should.

How do I get a heat pump?

Does a heat pump sound like the perfect solution to increase your comfort at home and save money every month on your utility bills? Co ntact us for a no-obligation heat pump home assessment, and let our trusted Daikin experts help you find the best heat pump for your home!