The latest cold climate heat pumps are helping us move away from fossil fuels for home heating & cooling. Heat pumps operate at a remarkable 200% to 300% efficiency. They are the most efficient and effective heating and cooling systems available to replace or supplement existing HVAC in our homes. Installing a heat pump will save you money and help us all maintain a livable planet for our children and grandchildren.
It’s up to all of us to take climate action now – and governments around the world are offering plenty of incentives to help us do it.
In this article:
- What are heat pumps?
- We now need air conditioning in northern climate zones
- The big picture – transitioning to clean energy
- Governments are paying us to switch to heat pumps
- Our transition from oil-fired boiler to heat pumps at Stonehaven
What are Heat Pumps?
Heat pumps are often compared to refrigerators that work in reverse. Yes, but there’s a bit more to it. The best explanation I’ve found for why heat pumps can be up to 300% efficient comes from the NYT Thom Dunn’s Wirecutter article:
“Heat pumps are essentially two-way air conditioners. In the summertime, they work like any other AC unit, removing heat from the air inside and pushing cooled air back into the room. In the cooler months, they do the opposite, drawing heat energy from the air outside and moving it into your home to warm things up. The process is especially efficient, using half as much energy on average than other electric home-heating sources. Or, as David Yuill of the University of Nebraska–Lincoln told us, “You could put in a watt of electricity and get four watts of heat out of it. It’s like magic.”
Unlike magic, however, there’s actually a very simple explanation for this result: Heat pumps have only to move heat, instead of generating it by combusting a fuel source. Even the most efficient gas-powered furnace or boiler never converts 100% of its fuel into heat; it’s always going to lose something in the conversion process. A good electric-resistance heater gives you 100% efficiency, but it still has to burn watts to produce that heat, whereas a heat pump just moves the heat. A heat pump can save you, on average, nearly $1,000 (6,200 kWh) a year compared with oil heat, or about $500 (3,000 kWh) compared with electrical heating, according to the US Department of Energy.”
There are three main types of heat pumps – each with their own pros & cons.
- air source (heating & cooling)
- air to water (heating only via hydronic systems)
- geothermal (heating & cooling)
Air source systems capture heat from cold air while ground source (geothermal) heat pumps capture the heat from below gound or an available water source. Geothermal systems are by far the most efficient to operate but they are also the most expensive to install.
This article focuses on air to air (air source) heat pumps. They are the best option to convert or supplement existing home HVAC (Heating, Ventilation, Air Conditioning) systems at a reasonable cost. There are two variations of air source heat pumps – Ducted and Ductless, sometimes referred to as a mini-split. An energy advisor will need to asses your current HVAC system to determine which type of system will suit your home and budget.
Ducted Heat Pumps
Ducted heat pumps use existing forced air furnace or air conditioning ductwork. If your home has existing ductwork in good condition, integrating a highly efficient heat pump into the system will likely be the best solution for your home. The Heat pump condenser unit is located outside the house and connected to your ductwork. Your existing oil, gas or electric furnace can be left in place and relegated to backup heat in extremely cold weather.
Besides saving money to heat your home, you’ll also enjoy central air conditioning to cool your home on those hot summer days.
Ductless (Mini-Split) Heat Pumps
Ductless heat pumps are the answer for homes that aren’t currently heated by a forced air furnace. Mini-split heat pumps consist of an outdoor condenser unit and an indoor wall-mounted ‘head’ connected by insulated flexible copper tubing call a ‘lineset’. Mini-splits are perfect for older houses and homes that have electric or hot water baseboard radiators because the linesets are typically run on the exterior of the house. Depending on your heating & cooling needs, a single outdoor condenser unit can be connected to up to 4 indoor heads mounted in key areas throughout the house.
Specifying and installing heat pumps require experienced refrigeration technicians and tools to ensure there are no kinks or leaks in the lines and that they are properly charged with refrigerant. It is not recommended to take this on as a DIY project.
Some home insurance providers require you to maintain your existing heating system as backup for your heat pump. Be sure to check to see if your insurance will be affected if you intend to remove your existing system.
Increased Air Conditioning Needs in Northern Climate Zones
Here in Canada, fewer than 50% of homes have central air conditioning with around 60% of all homes using some form of air conditioning – including less-efficient window-mounted room air conditioners. With the changing climate, there’s an increasing need for air conditioning in the summer months in places that previously could go without it.
We’re already experiencing asphalt-buckling temperatures in the southern US and western Canada.
Going forward, demand for air conditioning as well as heating will continue to move northward. We can help offset the increasing demand for electricity by insulating and air sealing our buildings and replacing oil or gas furnaces and baseboard radiators with heat pumps that will both heat and cool our homes much more efficiently.
The Big Picture – Global Transition to Clean Energy
It’s now been over 50 years since the early warnings on climate change were first brought to light.
Mitigating climate change is a complex problem to solve and we’re decades behind on taking collective action. Transitioning the world from fossil fueled energy sources (oil, natural gas & coal) to clean energy sources such as solar, wind, hydro and (eventually) nuclear fusion requires simultaneous advances in two areas:
- converting our energy demand such as cars, appliances & furnaces from fossil fuels to electricity
- converting electricity generation to clean, renewable sources with large-scale battery storage
Both aspects of our clean energy transition are important. Conserving energy by switching to LED lighting and converting our personal energy demands from gas & oil to electric cars, electric appliances, and heat pumps, moves us towards our goal – even if the electricity we use to charge our car currently comes from fossil fueled power plants. Some skeptics claim charging electric cars with fossil fueled power doesn’t make any sense.
The fact is, those power plants will gradually be replaced by clean energy sources with large scale battery backup storage in the near future. We’ll be able to smoothly transition to clean sources as they come online.
As individuals, we can’t just sit back end wait for others to do something. That’s why governments around the world are offering incentives to help us take the steps we all need to do now to minimize the dangerous effects of a warming planet.
Governments Are Paying Us to Switch to Heat Pumps
US Heat Pump Rebate Programs
The Inflation Reduction Act signed in 2022 by the Biden Administration includes significant funding for climate initiatives designed to help households transition to clean energy. These initiatives offer tax credits and significant point of sale rebates deducted at the time of purchase. Lower income households may qualify to get a heat pump installed at no cost so don’t wait to look into this opportunity.
Check to see if your state also offers programs that can be accessed along with the federal ones.
For more information:
Vermont and Maine offer excellent examples of information portals for anyone considering the transition to heat pumps in northern US states.
Canada Heat Pump Rebate Programs
Similar provincial and federal rebate programs are available here in Canada. Guidance for application recommends homeowners apply for the provincial program first – through one of the approved local licensed energy audit services. The provincial energy audit program co-ordinates information with the federal program.
A new federal grant program is about to start in January 2023. The Oil to Heat Pump Affordability (OHPA) Grant provides funding for qualified applicants to switch from oil furnaces to heat pumps at no cost to them.
Now’s the time to get at the head of the line to take advantage of these money-saving programs.
Stonehaven Oil to Heat Pump Transition
Last summer, two local news stories set off alarms for us:
- home heating oil prices spiked to $2.86/litre in June ($8.09/gallon USD)
- a forecasted rise from 8 to 42 summer days above 30C (86F) in the years ahead
Yikes!
We needed to change how we heat and cool our 130 year old farm house in Maritime Canada.
Over the years I’ve upgraded the windows & doors, added insulation where possible, air sealed most of the cracks and completed a passive solar porch reno. Our high-efficiency oil-fired boiler is about 12 years old and feeds hot water baseboard radiators throughout the house.
I reviewed my furnace oil bills from the past couple of years and found I used an average of close to 2000 litres/year to heat our home. At around 1.00/litre that was manageable. At 2.86/litre…uhhh, no.
Most summers we can manage the few very hot days by keeping the windows & blinds closed during the day to keep the heat out and opening it up at night to cool the house down. This becomes a losing battle when you get several humid days in a row above 30C as we did several times last summer.
While getting a quote from a reputable heat pump contractor he also informed me of the provincial and federal programs we’d be eligible for. Initially I was simply going to add one unit to supplement our existing oil boiler, but the benefits of relegating the oil furnace to backup heat made more sense.
Our cold climate heat pump setup:
- 1 Daiken Aurora 12,000BTU compressor with a single head (kitchen)
- 1 Daiken Aurora 36,000BTU multi-head compressor with three heads (living room, 2nd floor, basement)
The Greener Homes Program requires a minimum of 1 head per floor and we did need to have one in the basement to keep the boiler pipes from freezing. It will also dehumidify the basement in summer.
Installed, the cost of the heat pumps was slightly over $19,000 CDN including 15%HST. The Greener Homes Program rebate was $5400 CDN (which included a full rebate for my out of pocket cost for the home energy audit required to be eligible). The Provincial rebate was $1450 CDN for a total of $6850 in rebates or almost 35% of the cost.
The heat pumps were installed in September when the nights were getting cooler. We adjusted the temperature for each unit over the first week or so and have been running them on ‘set it and forget it’ ever since. Each head has adjustable fans and fins to aim the outflow if required. They provide consistent heat throughout the house without any temperature fluctuations.
So far this winter we haven’t had any extremely cold (-20C to -30) weather that would really test the capabilities. We can always fire up the oil boiler to assist if needed – setting the thermostats a few degrees below the heat pump temperature. The oil boiler will also serve as emergency heat since it’s already wired to safely operate off our portable generator during a power outage.
Here are a few things I learned from my experience:
Interior Head Location
It was relatively easy to determine the locations for the interior heads of our ductless mini-split heat pumps. Ideally, the heads are located about 8″ from the ceiling and project the airflow along the longest path available. On the first floor we have one head in the living room at the front of the house and one in the kitchen at the back of the house. The basement head is located in the centre for the best coverage throughout.
On the second floor, sloped upper walls and a long narrow hall leading to several small rooms left us only one option. We placed the second floor head in the only practical place – a narrow triangle of wall beside a window in the hall at the top of the front stairs. By running the fan for this unit at a higher speed and with additional heat rising from the back stairwell off the kitchen, even the bathroom at the back of the house is a comfortable temperature.
Dehumidify Function
Besides heating and cooling, heat pumps will act as a dehumidifier. Summer humidity makes the air feel warmer so simply reducing the humidity will make you more comfortable and use even less energy. The moisture collected from the air drains outside by gravity through a condensate tube. A small condensate pump is connected to any drain lines running through the basement that may be lower than where they exit the house.
Snow Covers / Snow Clearing
In northern regions you’ll likely need to buy or build snow covers to protect your compressor from snow and ice falling off the roof. Compressors require about a foot of air space between the unit and the exterior wall of your house – placing it directly under the roof drip line. Gutters will help to some degree but a proper cover will prevent cumulative damage througout it’s service life.
Be sure to keep snow and ice from accumulating below and around your compressor. Cold climate heat pumps need access to lots of air to function properly. They have an automatic defrost cycle that breifly reverses the operation – sending warm refrigerant to the outddor unit to melt frost and ice that can accumulate on the condenser coils. Any water dripping off will freeze and can build up over many cycles so be sure keep the space below the unit as clear of snow as possible.
Outdoor Compressor Location
Curb appeal is an important aspect of the value of your home. Work with your contractor to determine the most appropriate location for mini-split compressors & linesets before they start the installation. Don’t just let them to choose a location that’s most convenient for them.
The aesthetics of heat pump compressors and lines running on the house exterior to the heads were one of my concerns. Based on the locations of the interior heads, the contractor suggested locating one compressor on each side of the house. That setup would have placed the larger compressor that feeds three heads in the most visible location next to the driveway. Add electrical shutoffs, 3 linesets running in all directions and topped off with a snow cover I was concerned about how ugly it would be.
After a few days of considering the options, I suggested an alternative installation setup that would locate both compressors on the back side of the house. This required running one of the linesets through the basement between the floor joists to reach a head located on the driveway side of the house. We were able go with this setup and it works just great. The compressors and linesets are completely out of sight unless you are in the backyard. Perfect.
Already Saving Money
We’re halfway through our first winter with our heat pumps and we’re very happy with our decision. The extra money we’ve spent on our electric bill is less than half of what we would have spent on heating oil at current prices. When spring rolls around we can shut the heat pumps off. But we’ll have them available to keep the house cool on those hot & humid summer days ahead.
