Bard 920-0074 qwserv manual Electrical Specifications, General Description, Control Requirements

ELECTRICAL SPECIFICATIONS

			Control
Model	Voltage	Amps	Voltage
920-0074	230 / 208	2.2	24V

	For Use with the
Model	Following Units
	QW2S-A, -B, -C
920-0074	QW3S-A, -B, -C
	QW4S-A, -B, -C
	QW5S-A, -B, -C

GENERAL DESCRIPTION

The Energy Recovery Ventilator was designed to provide energy efficient, cost effective ventilation to meet I. A. Q. (Indoor Air Quality) requirements while still maintaining good indoor comfort and humidity control for a variety of applications such as schools, classrooms, lounges, conference rooms, beauty salons and others. It provides a constant supply of fresh air for control of airborne pollutants including CO2, smoke, radon, formaldehyde, excess moisture, virus and bacteria.

The ventilator incorporates patented rotary heat exchange state-of-the-art technology to remove both heat & moisture and provides required ventilation to meet the requirements of ASHRAE 62.1 standard.

It is designed as a single package which is factory installed. The package consists of a unique rotary Energy Recovery Cassette that can be easily removed for cleaning or maintenance. It has two 15-inch diameter heat transfer wheels for efficient heat transfer. The heat transfer wheels use a permanently bonded dry desiccant coating for total heat recovery.

Ventilation is accomplished with 2 blower/motor assemblies each consisting of a drive motor and dual blowers for maximum ventilation at low sound levels. Motor speeds can be adjusted so that air is exhausted at the same rate that fresh air is brought into the structure thus not pressuring the building. The rotating energy wheels provide the heat transfer effectively during both summer and winter conditions.

NOTE: Operation is not recommended below 5°F outdoor temperature because freezing of moisture in the heat transfer wheel can occur.

CONTROL REQUIREMENTS

1.Indoor blower motor must be run whenever the ERV is run.

2.Select the correct motor speed on the ERV. Using Table 1 of the ERV Installation Instructions determine the motor speed needed to get the desired amount of ventilation air needed. For instance, do not use the high speed tap on a ERV if only 200 CFM of ventilation air is needed. Use the low speed tap. Using the high speed tap would serve no useful purpose and would effect the overall efficiency of the air conditioning system. System operation costs would also increase.

3.Run the ERV only during periods when the conditioned space is occupied. Running the ERV during unoccupied periods wastes energy, decreases the expected life of the ERV, and can result in a large moisture buildup in the structure. The ERV can remove up to 60 to 70% of the moisture in the incoming air, not 100% of it. Running the ERV when the structure is unoccupied allows moisture to build up in the structure because there is little or no cooling load. Thus, the air conditioner is not running enough to remove the excess moisture being brought in. Use a control system that in some way can control the system based on occupancy.

NOTE: The Energy Recovery Ventilator is NOT a dehumidifier.

IMPORTANT

Operating the ERV during unoccupied periods can result in a build up of moisture in the classroom.

Manual 2100-533A

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