- Gold LEED Certification Level
- Triovest Realty Advisors C/O Green Reason Inc. Building Owner
- Integral group MEP Engineer
- Owner Mechanical Contractor
- Owner General Contractor
720 King Street West is a multi-faceted building in the heart of Toronto. Situated in the middle of both a residential and a commercial neighborhood the building provides a convenient downtown location for leasing. The ground floor offers convenience for the locals - banks, florists, coffee and fast food. The remaining nine floors are occupied by the workforce of multiple tenants such as a bank corporation, a call center, a dental office and a pharmaceutical research facility.
Built in 1976, the building has undergone two major renovations. In 1999 the building was provided with a new HVAC system which included three hundred VVT boxes, one hundred new heat pumps as well as upgrades to the existing heating and cooling plants. The renovations brought over one thousand tons of cooling to the floor spaces. The heat pumps were strategically placed in mechanical rooms on each floor which also serve as a mixing plenum for the return and outside air streams. The mixed air is then conditioned by the 2 stage heat pumps and delivered to the associated VVT terminals on the floor.
The original HVAC systems did not operate on their own. Operators had to manually monitor devices and make adjustments to maintain comfort. Tenant feedback was routinely used to identify failures in the systems. The owners recognized the need for a Direct Digital Control system in order to monitor the operation of the HVAC equipment, and in late 2009 one was installed. The mechanical systems that were controlled and monitored under the Building Automation included the major heating and cooling plants as well as the heat pump and VVT terminal units.
However, the new building automation did not perform as expected. The existing system lacked performance in the following aspects:
1. Indoor Air Quality: The mixing of fresh air and return air in the mechanical rooms did not function as anticipated and as a result, floors routinely experienced poor air quality and high CO2 levels.
2. Distribution of Indoor Air: The VVT boxes allowed for heating and cooling of the space but did a poor job of regulating the amount of air throughout the floor. As a result certain areas were receiving less air than anticipated.
3. Controller Memory and Storage: The existing controllers did not have the capacity to store large amounts of data or provide rolling historical data. As a result the operators were forced to reset the controllers monthly.
In early 2013, Green Reason, an independent consulting company that works directly with owners, took initiative to correct some of the issues surrounding the BAS at 720 King Street. The approach was to pinpoint the problematic areas and come up with a solution that did not require a complete overhaul of the HVAC system. Then partner with a skilled controls contractor to implement the latest techniques for optimization.
Once awarded with the contract, HTS faced multiple challenges that needed to be overcome in order to deliver the system on time and on budget. Challenges included retrofitting an occupied building while minimizing downtime and also integrating foreign systems with different communication protocols into one complete BAS.
HTS started by installing the latest ACM supervisor controller and added controllers to the air handling and terminal units. To complete the system HTS used an Alerton LON integrator to integrate the existing Trane heat pump controllers into the BAS for monitoring and control. A graphical analytics package was added to complement and display the operation of the building. Damper actuators were also added on the return air dampers to correct the CO2 issues.
Positive feedback was received from the tenants at the early stages of the renovation and the work was performed with minimal disruption to the tenants. HTS seamlessly upgraded the existing control system with new devices and integrate the heat pumps into the BAS.
The high CO2 levels were corrected and proper ventilation was achieved by controlling the new actuators on the return air dampers. Tenants now experience an increase in workforce energy and productivity. The building operator no longer has to continuously monitor the systems and is finding the new BAS to be very intuitive and easy to use.