Bryant 549C Application Data, Concentric Duct Distribution 542J150,180, Description Environment

APPLICATION DATA (cont)

a50-6549

NOTES:

1.Do not drill in this area, damage to basepan may result in water leak.

2.A 90-degree elbow must be provided in the supply ductwork to comply with UL (Underwriters Laboratories) codes for use with electric heat.

Concentric Duct Distribution — 542J150,180

1'-10 11/16''	6'-2 3/8'' MAX.
MAX.	5'-9 3/16'' MAX.

5 3/16''

4'-6 13/16''1'-0 3/16'' 1'-7 15/16''

1'-0 3/16''

B

B

24'' MIN.

A

A

BAFFLE a50-530

Shaded area indicates block-off panels.

NOTE: Dimensions A, A′ and B, B′ are obtained from field-supplied ceiling diffuser.

CAUTION: Concentric ducts may only be installed on units without electric heat. Personal injury or unit damage may result.

Concentric Duct Details — 542J150,180

CONDENSER COIL PROTECTION APPLICATIONS

DESCRIPTION						ENVIRONMENT*
(Enviro-Shield™ Option)			Standard, Non-Corrosive	Mild Coastal	Moderate Coastal		Severe Coastal	Industrial	Combined Coastal and Industrial
Standard, Al/Cu			X
Pre-Coated Al/Cu				X
Cu/Cu						X
E-Coated Al/Cu								X	X
E-Coated Cu/Cu							X
				LEGEND
Al/Cu	—	Aluminum Fin with Copper Tube Coil		E-Coated		— Extremely Flexible and Durable Epoxy Coating Uniformly
Cu/Cu	—	Copper Fin with Copper Tube Coil		Pre-Coated		Applied to the Coil Surfaces
Enviro-Shield	—	Family of Coil Protection Options				— Epoxy Coating Applied to Fin Stock Material

*See “Selection Guide: Environmental Corrosion Protection” Catalog No. 811-217 for more information

15.ECONOMI$ERIV — The EconoMi$erIV factory-installed economizer package includes a gear-driven damper system that modulates the return air and outdoor air supply to the rooftop unit in order to take advantage of “free cooling” with outdoor air when conditions are suitable. The system utilizes industry proven technology available for integrating the use of outdoor air for cooling with mechanical cooling for 3 through 15-ton rooftop units. The intuitive EconoMi$erIV solid-state controller optimizes and enhances rooftop operation through reduced energy consumption, optimal zone comfort, and effi- cient equipment cycling. This is accomplished by operating the compressors when the outdoor air temperature is too warm, integrating the compressors with outdoor air when free cooling is available, and locking out the compressor when outdoor air temperature is too cold. The detailed sequence of operation is described in the controls section with a brief description of selected application items here.

Thermostat Interface — The EconoMi$erIV control was designed to work with conventional thermostats that have Y1 (cooling stage 1), Y2 (cooling stage 2), W1 (heat stage 1), W2 (heat stage 2), and G (fan). In addition, the EconoMi$erIV will support an occupied/unoccupied switch (typically integrated into the thermostat or thermidistat). When the switch is closed, it provides a 24 vac signal to the unit for occupied mode, and provides no signal to indicate unoccupied mode. The EconoMi$erIV control can be con- figured to allow different minimum economizer damper posi- tions and to allow the use of mechanical cooling in the occupied mode.

Control Features — The EconoMi$erIV controller provides superior functionality for rooftop unit operation. EconoMi$erIV control features are included as follows:

Remote minimum position control — The EconoMi$erIV controller can be used with a field-supplied and field- installed remote minimum position control switch that will enable and disable the EconoMi$erIV to open or close the damper beyond the minimum position for modified ventila- tion, providing 2 to 10 vdc output.

NOTE: Minimum position signal takes priority over the DCV (Demand and Control Ventilation) maximum position signal.

Demand control ventilation (DCV) — The EconoMi$erIV has DCV capability when using an IAQ sensor. This sensor is typically installed in the return duct or occupied space. When implementing a DCV control scheme with the EconoMi$erIV, the control algorithm will modulate the posi- tion of the damper between two user-configured damper positions, Maximum DCV Position and Minimum Occupied position. Design airflow rates for these two damper posi- tions should be such that when the damper is at the Maxi- mum DCV position, enough fresh ventilation air will be brought in to remove contaminants and CO2 generated by sources other than people (i.e., since in unoccupied mode). The Maximum DCV position is intended to satisfy the IAQ “Base Ventilation Rate.” The Minimum Occupied position design airflow rate should be sufficient to satisfy ventilation requirements for removing CO2 from all sources including people at the maximum occupancy.

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