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My neighbour got a fancy new heat pump. Should I get one too? Heat Pumps vs. Furnaces

a freshly installed heat pump condensing unit beside an old home
A modern, inverter driven, cold climate heat pump.

  1. Climate considerations

  2. Oversized Gas-Fired Equipment

  3. Modern Heat Pumps for Modern Homes

  4. Ducted vs. Ductless

  5. Gas Meter vs. Electricity Meter

  6. Request a Quote

So your neighbour got a fancy new heat pump and can't stop talking about it, and you want to know if you should follow him down the electrification rabbit hole. are not the only one looking at the available grants and climate research and thinking the same thing. We get lots of calls from people looking to compare a new heat pump vs, their old furnace.

1. Climate Considerations:

In order to meet our commitments to reduce greenhouse gas emissions, Canadians are being incentivized by all levels of government to ditch fossil gas sources of heat. For most homes, modern, inverter driven, cold climate, air to air heat pumps will be the best alternative to the fossil gas (propane, or methane) furnaces and boilers that are currently installed and working to heat Canadian homes. There are loads of rebates available through the federal government, BC Hydro, and Fortis that will help make this transition more affordable. The question is.. should you take the bait.

And as with many things the answer is more complicated than just yes, or no, because, while modern heat pumps are amazing pieces of technology, there are still some potential downsides.

2. Oversized Gas-Fired Equipment:

Firstly, your furnace is likely oversized for the amount of heat that your house looses on the coldest day of the year, and while this is wasteful to a certain extent, it means that there is loads of margin to keep the house warm or to warm it up quickly when it gets cold because you left a window open or whatever.

The cold climate heat pump that would be sized to your home would likely be right sized for the job of keeping your house warm or cool on the hottest and coldest days of the year, and because of this, there is less margin of error, and instead of overshooting the set-point on the thermostat and only running for 20 minutes out of every hour, will likely have to run almost constantly on those ultra cold or ultra hot days.

There are very few of those days every year, and so it will be much more efficient on average, but kind of like the range anxiety that people who first buy electric cars experience, some people who get a heat pump wonder: "will it keep up?" If it has been sized correctly and is operating properly, it will keep up, but it will be closer to the line than a furnace would be.

3. Modern Heat Pumps for Modern Homes:

If your home is a modern, airtight and well insulated home to begin with, or if your have already put it through some of the steps of a deep energy retrofit then a heat pump will probably be perfect. Modern, inverter driven heat pumps can modulate from 125% of their rated range, all the way down to 10% or lower. This means that if your home has a smaller heat loss or heat gain as a modern home will, then the heat pump's slower pace of heating will be perfectly suited to keep everyone comfortable, even on super cold or hot days. Modern homes will likely be EVEN more comfortable with a heat pump than with gas heating equipment because furnaces emit 40,000 btu per hour (BTU is a measure of heat) at the smallest. and if a home is only loosing 2000 btu per hour, then the furnace would only have to run 5 percent of the time to keep up. This would result in many parts of the house, not near the thermostat that would be uncomfortably cold.

The opposite is true too. A leaky Edwardian mansion, with ancient sash windows, will loose heat too fast for most heat pumps to keep up. And it would be hard to oversize a furnace for this home on the coldest days (ductwork considerations aside).

4. Ducted vs. Ductless:

The next consideration, is that if the system you are looking at is a ducted system to connect to the existing duct system in the home and formerly served by the furnace and AC, then we have to find out whether the ductwork is sized appropriately for the heat pump. Modern heat pumps have variable speed fan motors and can operate across a wide range of airflow settings, but in order to run at its maximum on those hot and cold days, the ductwork will need to be pretty big. One ton of heating from a heat pump needs about 400 cubic feet per minute of air, as much as double the air that an older furnace would need for the same heating capacity.

When Crux Mechanical Ltd. quotes a heat pump, we take accurate measurements of the ductwork that already exists in the home and we plug it into our airflow model to make sure that the new equipment will function as designed and won't create a nuisance with excessive noise from trying to flow too much air through small, old sheet metal.

For homes that are getting a modern, cold climate heat pump system with ductless heads (wall mount or cassettes), Crux Mechanical will make sure that the heads are installed on walls or in ceilings, where they can offer the maximum range and throw to cool the spaces evenly. But when installing a 4 zone ductless system in a house that has 12 rooms, some spaces are going to be left without the control that those used to central heating systems are used to. That doesn't mean that the leftover rooms won't be comfortable, just that their comfort will be harder to control.

Four different styles of mini -split heat pump indoor heads: ceiling cassette, wall mount, floor mount, and slim duct. Each head displayed in its proper orientation and location.
Mini-Split Indoor Head Styles - courtesy of Fujitsu.

The last drawback is cost. These cold climate heat pump systems are very costly to purchase and install compared to their fossil gas equivalents. Most furnaces are very simple machines, and quite cheap to produce and install (well, by comparison anyways).

5. Gas Meter vs. Electricity Meter:

In British Columbia, electricity is more metered at higher rates than fossil gas from Fortis, and so heat pumps are, on average, more expensive during heating season than a gas furnace. Some of that cost is made up in summer, because when in AC mode, cold climate heat pumps are more efficient than a standard air conditioner.

Will electricity prices always be more expensive than methane from the gas company, probably not. Given the pressure to get climate change under control, this will probably have to flip at some point. But it is hard to say when.

So you must be wondering whether we are trying to un-sell you on the idea of a heat pump, the answer is definitely no. We love these machines. They were developed in Japan during the roaring 90's just like Lexus and the DVD, and just like a Lexus, the modern, cold climate heat pumps is an engineering marvel. When installed correctly, they can run flawlessly for years, and require nearly no maintenance, besides the occasional coil cleaning and filter changes. Moreover they are challenging and super fun to install, which our teams like. What we don't want is for people to get halfway down the path of deciding they want to replace their furnace with a heat pump and then balk at the cost. Or worse, get the heat pump installed, and then find the slightly lower level of heat delivered to be uncomfortable.

6. Request a Quote:

If you are thinking about a heat pump, we sell and install loads of them every year, and would be happy to guide you through the process, from sizing, and selection through head location, and the finer points of the Canada Greener Homes Grant. Fill in our request for quote form and we will be in touch.

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