Parson Refrigeration Leads with Newer Technologies: Large CO2 Projects
In 2019 we were awarded the largest refrigeration project that we had ever undertaken. The Sysco Tannis Warehouse project was an expansion of 125,000 square feet of refrigerated space. We were responsible to design, supply, install and commission the complete refrigeration system.
The client’s typical warehouse would use ammonia as a refrigerant, at our recommendation they accepted a refrigeration system using CO2 as the refrigerant. At the time of the contract award, it was their first CO2 refrigerated warehouse in North America.
With our equipment supplier partners, we provided our client with an energy efficient, environmentally superior, made-in-Canada solution for the refrigeration equipment design. Our suppliers include: System LMP, Laval Quebec; Ref-Plus, St. Hubert Quebec; Keeprite Refrigeration, Brantford Ontario.
The installation was handled by an Ottawa-based team of contractors including BBS Construction as the general contractor, Dry core Electric, Dilfo Mechanical and ourselves. The construction required extensive coordination between all trades to get the system operational.
Click on a sub-heading below to display related text and photos.
Compressor Room
This room houses the six LMP trans critical R-744 compressor racks, there are four low temperature units that operate the freezer and two medium temperature units that operate all the medium temperature refrigerated spaces. Each compressor rack is completely independent of each other to provide redundancy in the event of a breakdown. They total over 1000 nominal horsepower.
Control Room
Due to the size of the refrigerated warehouse, it was highly beneficial to locate a power distribution room and control room mid-point in the building. All the freezer air handlers and evaporator coils were fed through the control panels and all input sensors for system control were wired back into their respective control boards.
Coolers
The medium temperature coolers comprise approximately one half of the total expansion. Different areas are designed to hold temperatures from +1 C to +10 C depending on the type of product being stored. Conventional evaporator coils are hung from bar joists for air distribution.
Freezer Penthouse
The freezer area was designed with an evaporator penthouse to house the large evaporator coils, with this design the evaporator coils are kept out of the freezer area which allows for more shelving to be installed and make the coils much easier to service. Each coil provides 12.5 tons of cooling at 10 F TD, and moving 29,500 CFM of air.
Under Floor Heating
To prevent frost from entering the subfloor of the building heating loops are installed on grade and glycol is pumped through the tubing to add heat. The heat is recovered from the refrigeration system discharge lines and recycled to maintain the underfloor soil above well above the freezing temperature.
Gas Coolers
The gas coolers are used reject the heat that was removed from the refrigerated spaces to atmosphere. There is one gas cooler per compressor rack, due to the higher pressure on the discharge lines all piping is run in stainless steel.
Loading Dock
The medium temperature coolers comprise approximately one half of the total expansion. Different areas are designed to hold temperatures from +1 C to +10 C depending on the type of product being stored. Conventional evaporator coils are hung from bar joists for air distribution.
Testimonial
Working on a project the size of the Sysco Warehouse was a great challenge that put all our abilities to the test — from receiving and installing the massive evaporator coils and putting together the pieces for the 16 air handling units that supply the freezer with cooling. We also had an opportunity to connect and commission the entire control system. The whole job was on a different scale.
The knowledge that was gained from working on such a large CO2 refrigeration system is invaluable experience. It’s the kind of project that may only happen once in a career and I’m glad I was part of it.
M. Leclerc
Parson Refrigeration (1985) Ltd.
