Condos: Expanding the VRF Universe
By J.S. Rancourt
Variable refrigerant flow (VRF) HVAC systems are no longer considered a new thing. It has been more than a decade since the first major global alliance was forged between a large Japanese VRF manufacturer and a North American HVAC manufacturer. Since then, numerous global alliances have been forged, and system offerings have increased throughout North America.
As a result, there are now large office buildings, schools, churches, government buildings, medical buildings and, as detailed in my last article (see Mechanical Business Nov./Dec. 2015), a very large hotel in Canada that are using VRF for their main HVAC systems.
There is precedence, there is track record, there is adoption; so what’s next for this technology? How about the condo industry?
As a matter of fact, there are currently a couple of landmark condo projects in the Greater Toronto Area under construction that will be using air-source VRF as their sole means of space heating and cooling.
Why did it take until now to look at the residential market, and why do we now predict that the next big thing for VRF will be in the condo industry? The answer revolves around two main points: reduced capital costs of VRF systems and new energy efficiency requirements.
Getting the Developers’ Attention
Technological advancements that do not result in construction cost savings usually need to have a meaningful impact on the salability or value of the units for a developer to consider them. Since homebuyers are more likely to be swayed by a high-end countertop than a high-end HVAC system, the first driver for the general adoption of VRF by condo developers will most likely be based on the capital costs—which were more considerable five or 10 years ago—no longer being a large premium when compared to conventional systems.
The capital cost of a VRF system, or of any HVAC system for that matter, is driven by two main things: equipment cost and installation costs.
With VRF numbers on the rise in Canada, and with more manufacturers offering this type of equipment, the price has dropped significantly. I’d estimate that VRF equipment prices are close to half of where they were just 10 years ago.
Of course, equipment cost was never the primary issue in the salability of VRF in condos. The installation cost and complexity of the systems – or at least, the perceived cost and complexity –was perhaps a bigger road block.
A large proportion of mechanical contractors who install HVAC systems in condos have developed a comfort zone with the standard, water-based heating and cooling systems they have been installing. This can put them in a difficult position if a developer opts for a refrigerant-based VRF system. This change to the status quo can take a leap of faith for the mechanical contracting firm, and may require some additional training.
On the cooling side, the efficiency story for VRF technology stems from the part-load efficiency of inverter compressors and in fewer heat exchanges that are present than in traditional HVAC systems.
On the heating side, the COP of VRF averages between 3 and 4 over the winter. Considering that the COP of a furnace is always below 1, no matter how efficient it is, it should not be surprising that VRF is attracting attention.
A Green Approach
As politicians come up with policies aimed at de-carbonizing the Canadian economy, VRF technology could be a viable solution for comfort systems as all space heating can be accomplished without the use of fossil fuels. VRF is a technology that can help us make use of our electrical grid for heating in a very efficient manner, due to the COPs, and this grid continues to get greener as utilities move to green options for generation, like wind, solar and other renewable energy sources. As such, VRF allows us to keep reducing our carbon impact.
Set to be completed in the spring of 2018, The Jack is an 11-storey condo from Aspen Ridge Homes located just off of Yonge Street, south of St. Clair.
The architectural beauty will feature a pair of large penthouses on the 11th floor, each served by its own dedicated VRF system. The rest of the spacious 100-plus units will be served by one of 20 heat recovery VRF systems located on the roof.
The VRF units are sized to meet both the cooling load and the heating load at the local design temperature of -20°C, with an assurance that the units can operate down to -25°C. To service the various condominium units, a mix of horizontal and vertical VRF fan coils will be used.
The Efficiency Picture
The VRF story in condos does not only revolve around capital cost savings. What is bringing VRF to the table, and what will continue to bring VRF to the table more and more, are increasing energy efficiency requirements in many parts of the country.
For example, when applying for a building permit in Ontario, there are two general paths that can be followed to ensure that the project is in compliance with the energy efficiency requirements of the Ontario Building Code.
One is based on the energy cost of the building, as compared to a standard building. The other is based on the energy use of the building, again as compared to a standard building.
The latter ignores the sometimes volatile economics of the energy sector, and simply looks at how many units of energy the building consumes. This is where VRF technology can be attractive, given the COPs that VRF heat pumps deliver.
And some of the newer VRF systems on the market can now operate efficiently at temperatures as low as -30°C, which increases the number of geographic zones where they can be an option for winter operation.
A short drive from downtown Toronto is Great Gulf’s Trafalgar Landing Condo project in Oakville. This set of three U-shaped four-storey buildings will make use of air-source VRF for all of their space cooling and heating needs.
The structures will be served by three different banks of VRF units placed on the roof; one per wing of each building. And each condo unit will feature a vertical VRV fan coil in a small closet. The project is well underway and will be completed this summer.