There are two cold, hard facts about working construction in Edmonton, AB. First, contract deadlines force contractors to work through the winter months to complete the project on time. Second, outside temperatures often drop below zero, so contractors need a heat source to keep the project moving forward.

These two truths were exemplified with the large renovation project of the Edmonton Art Gallery, currently underway in downtown Edmonton. The project deadline is October 2009. In order to stay on schedule, tradesmen worked inside the structure during the winter, even when outside temperatures dropped below -25° F.

Several onsite conditions had to be considered to select the right heater for the job. First, “The structure was very tight, and, once enclosed, this rules out direct fired heaters,” explains Dave Strijack, rental sales representative for 4-Way Equipment Rental. Direct fired units introduce moisture and harmful emissions into an enclosed structure and present a potential fire risk. Additionally, the gallery will house precious works of art, which added to the reasons for not using this heat technology.

This left indirect-fired heaters as the only option, but there were a few considerations for this as well. “The gallery building had a lot of nooks and crannies to heat, so air movers, which could blow around construction dust, would have been required to evenly distribute the heat from air heaters,” mentions Mark Williams, business development specialist for Wacker Neuson Climate Technology. “Additionally, the superintendent did not want heating ductwork on the floor.” The combination of a large, segmented structure with a significant temperature rise required made indirect fired air heaters a less efficient and less desirable option for this application.

Top

Hydronic Air Heat
Williams and Strijack recognized that Pureheat™ was the most efficient solution. Representatives from 4-Way had worked with the contractor in the past with this type of heating system, so the contractors were familiar with the technology.

The Pureheat™ hydronic air heater from Wacker Neuson Climate Technology is one of the most versatile units available. Using the Purheat™ heater in conjunction with Wacker Neuson Heat Xchangers™, it is capable of heating up to 1.7 million ft³ spaces with a 714,000 BTU-per-hour heater output.

For the Edmonton Art Gallery, 4-Way rented the contractor four Pureheat™ units with 16 HX200 Xchangers™. “The contractor’s best estimate for the building’s heating requirements was 4 million BTUs,” says Strijack. While the heat output of the heating units does not add up to the customer’s estimate, Williams and Strijack were confident they would efficiently heat the space.

Each unit was hooked up to the onsite natural gas supply. “The natural gas burner heats the glycol, which is sent through the hoses to the heat exchanger,” adds Williams. “The heated glycol runs through the heat exchanger’s coils, and the fan blows warm, dry air into the room.”

Ingenious Solution
There was only one remaining issue for 4-Way. Each Xchanger™ requires a glycol supply and a return hose to provide heat. “The contractor did not want the hoses running across the floors and up the stairwells,” recalls Strijack.

The building’s installed boiler/chiller system’s pipes gave Williams and Strijack and idea. “We worked with the onsite plumbing/heating specialist to tap into the boiler/chiller system’s piping,” says Williams. Two loops – one for supply and one for return – were cut into a remote section of the piping for the main building.

With Pureheat plumbed into the piping, workers can place the HX200 Xchangers™ where the heat is needed without long stretches of hoses on the floor. Even better, Pureheat is keeping the gallery at a consistent 70° to 75° F temperature throughout the building, regardless of the outside temperatures.

“The four Pureheat units are easily heating the four-story building, and they are not running that hard,” mentions Strijack. He also reports the contractor likes the consistent, reliable heat of Pureheat™. They are saving the customer money and time, allowing the project to stay on schedule.

Top