- News Blog
Posted by Benoit Maneckjee on 26th Feb 2018
In February we finally got to see our new line of Aaon CF heat pump condensers in action. The first of several new installations in Nova Scotia was comprised of four CF-20 outdoor heat pump condensers, each with two 10 ton refrigeration circuits connected to four of our DX2W-3 20 ton indoor split modules. This 80 ton installation is at the new Velo apartment building complex at 2300 Gottingen Street in Halifax which features 105 apartments, 9 retail spaces and a 2nd phase in the future expanding the complex by 50% requiring another 60 tons for a total size of 140 tons. The new Aaon rooftop condensers are much quieter, powerful and energy efficient than previously used condensers and monitoring data has shown that they are outperforming our projections, promising customers quicker payback, greater savings and longer expected longevity.
Four Aaon CF-20 Heat Pump Condensers up on the roof in Phase-1. They are used for heating, air
conditioning and domestic hot water production. Phase-2 will add another three units to the roof.
Three of four ThermAtlantic 20 Ton DX2W-3 Modules in rooftop mechanical room. Room has been fitted
for three more 20 ton units for the 2nd phase of construction for a total of 140 tons.
Photo showing the two 6" diameter low loss headers connecting rooftop to basement mechanical rooms.
Low loss headers make it possible for water to be distributed over 5 stories apart with virtually no
additional pumping power.
Basement mechanical room showing 1 million BTU natural gas boiler used for backup heat
and domestic hot water top-up.
Basement mechanical room showing three 175 gal buffer tanks used for both heating and cooling.
Basement mechanical room showing three pre-heat and three top-up domestic 120 gal hot water
indirect dual coil tanks. The first three tanks are preheated by the heat pumps between 100-120°F
during the winter and topped-up by the boiler loop as needed using the last three tanks.
The hydronic design we came up with for this project required us to locate the condensers up on the roof along with our DX2W-3 modules but keep the heavy and bulky storage tanks, domestic hot water and backup boiler in the parking garage mechanical room. This was accomplished by using a 6" diam low loss header to connect the rooftop and parking garage mechanical rooms along with a smaller 3" loop for domestic hot water preheat. Our building automation platform controls and monitors the eight 10 ton refrigeration stages, 1 MBTU natural gas boiler, 3 x 175 USG stainless steel buffer tanks, 3 x 120 USG stainless steel indirect water tanks for preheat along with another 3 x 120 USG stainless steel indirect tanks for domestic hot water top-up and storage and finally a snow melt system. Eleven Wilo Stratos Smart ECM circulators are used throughout the installation and feature dual heads for redundancy in all mission critical circuits.