Providing adequate heating and ventilation during the winter can be an expensive proposition for commercial HVAC systems and their associated utility costs. With lows in some parts of the country dipping below zero, maintaining comfortable temperatures and healthy indoor air quality between December and February can be expensive in commercial facilities.
Ventilation presents its own challenges as it is expensive to condition cold winter air being brought into a facility. But with the right equipment, spaces can still be kept comfortable and properly ventilated in the coldest months while minimizing costs.
Writing in Modern Restaurant Management, Richard Boothman, Director of North American sales at Modine, emphasizes that care must be taken to set the right conditions for success:
An important step is to ensure that the building is pressurized so that the system is not pushing out more conditioned air than it’s pulling in.
Set the volumes of the unit supply air and exhaust air to provide a slight positive space pressure and then make sure those settings are maintained. Building leakage isn’t good for efficiency or ventilation. Modine units can monitor building pressure and adjust fan speeds through a variable frequency drive, (VFD).
The biggest reason to provide a slight positive in most cases is to stop uncontrolled infiltration that causes uncomfortable drafty conditions as well as puts extra strain on the space conditioning equipment. The installation of a Dedicated Outside Air System (DOAS) can reduce energy costs by decoupling the outside air ventilation load from the space load and provide that positive pressurization to reduce or eliminate infiltration. Modine’s Atherion® Commercial Packaged Ventilation System is ideal for conditioning and tempering high volumes of outside air for ventilation and is effective in any climate in the United States. By conditioning the air before it enters the facility, the Atherion® can reduce the load on the interior HVAC system. Modine also offers Indirect or Direct Fired Heating Make-Up Air units that are focused on primarily heating but have options for evaporative, chilled water, or split DX cooling as well.
Coupled with an optional energy recovery module, the Atherion® can help reduce energy costs even further. Consisting of an aluminum energy-recovery wheel, the module works by recapturing energy from the exhaust air. In turn, that energy can be used to preheat or precool the outside air, leading to potentially thousands of dollars in savings in operating expenses over the course of a year.
Finally, Atherion offers gas, electric, or hot water heating options for maximum flexibility. The gas heat options have thermal efficiencies that range from the standard 81% up to condensing 94% with hybrid options in between that are up to 87% thermally efficient as a system.