Accessories

Economizer Control (Free Cooling)

Take advantage of cool outdoor air to handle space loads. A call for cool air is sent to the unit’s control center which triggers one of a few different options to bring in fresh cool air:

Energy Wheel On/Off

The wheel cycles off when it’s in the free cooling range (temperature or enthalpy), and cycles on when outdoor air is too warm or too cold. This option is recommended when the air is being supplied to an air handling unit or duct heater, and not directly to the space.

Energy Wheel Modulation

The wheel speed modulates to maintain a 55°F discharge temperature. Above 55°F, the wheel is off up to a high-limit temperature setting (typically 70°F). This option is recommended when the air is supplied directly to the space from the ERV or when more precise temperature control is needed.

Frost Protection

Cold climates, in combination with higher indoor humidity levels, may cause frost to form on the energy wheel during normal operation. To protect against frost, we measure the outdoor temperature and the energy wheel pressure drop. When it’s cold enough and the wheel pressure is increasing, the wheel is frosting. Only then will the frost methods described below engage. See the “Frost Control Strategy Recommendations” chart on this page for which of the three Greenheck frost methods we recommend for your building.

Timed Exhaust Frost Control

The supply blower cycles on and off based on a factory provided timer. With the supply blower off, the warm exhaust air melts the frost. Once the wheel pressure decreases, the supply blower turns back on.

Modulating Wheel Frost Control

A factory installed variable frequency drive (VFD) slows the wheel down making it less effective. In other words, the slow rotating wheel spends enough time in the warm exhaust airstream to melt the frost. Once the wheel pressure decreases,

it returns to full speed. Both blowers operate continuously during this frost mode. Modulating wheel frost control is available on all sizes except the ERV-251.

Preheat Frost Control

Frost Control Strategy Recommendations

Winter Outside Air

Winter Indoor Air

Recommended

Frost Control

Design

Design

Strategy

 

 

 

 

 

≥ 10°F (-12.2°C)

≤ 50% RH

None

 

 

 

-5°F(-20.6°C) <

≤ 35% RH

Timed Exhaust

10°F (-12.2°C)

 

 

 

 

 

≥ 10°F (-12.2°C)

≤ 50% RH

 

 

 

 

-5°F(-20.6°C) <

≤ 35% RH

Electric Preheat

10°F (-12.2°C)

 

 

 

 

 

-5°F(-20.6°C)

Any RH

 

 

 

 

An electric preheater is built into the ERV outdoor air intake. When frost occurs, the heater engages, and increases the outdoor air temperature above the frost threshold to melt the wheel. Once the pressure decreases, the heater shuts off.

The map at left indicates the frost control options, if any, that are appropriate based on climactic conditions during typical 16 hour per day operation.

Preheat Frost Control Recommended*

Timed Exhaust Frost Control Recommended*

No Frost Control Needed

*Modulating Wheel Frost Control can also be used in these areas.

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Greenheck Fan ERV manual Economizer Control Free Cooling, Frost Protection

ERV specifications

Greenheck Fan's Energy Recovery Ventilator (ERV) represents a significant advancement in the field of indoor air quality and energy efficiency. These systems are designed to provide balanced ventilation while recovering energy from exhaust air, making them an ideal choice for commercial and industrial applications.

One of the main features of the Greenheck ERV is its energy recovery core, which effectively transfers heat and moisture between the incoming and outgoing airstreams. This technology allows for a significant reduction in heating and cooling costs by pre-conditioning the incoming air, resulting in less strain on HVAC systems. The core is engineered for high efficiency, delivering seasonal energy savings and contributing to LEED certification for green buildings.

Another notable characteristic of the Greenheck ERV is its versatility. The units come in various sizes and configurations to meet different building specifications and ventilation requirements. They are suitable for a wide range of applications, from schools and offices to hospitals and industrial spaces. Users can customize the ERV to suit specific needs, including options for enhanced filtration, integrated controls, and multiple airflow configurations.

The construction quality of Greenheck ERVs is also commendable. They feature robust materials that ensure long-lasting performance and durability, even in demanding environments. The units are designed to withstand harsh outdoor conditions, making them reliable for year-round operation. Furthermore, the noise levels are minimized thanks to their well-engineered design, providing a comfortable indoor environment free of distracting sounds.

Greenheck has incorporated advanced controls and monitoring technologies into its ERV systems. This feature allows users to track performance, optimize energy use, and maintain indoor air quality. The controls can be integrated with building management systems for seamless operation. Moreover, the units are designed for ease of maintenance, with accessible components that simplify servicing and repairs.

In summary, Greenheck Fan's Energy Recovery Ventilator combines energy efficiency, versatility, and advanced technology to deliver exceptional indoor air quality solutions. Its energy-recovery capabilities, adaptability to various applications, durable construction, and advanced controls position it as a leading choice in the market for energy recovery and ventilation solutions.