Greenheck Single Duct VAV Terminals

Introduction

Please read and save these instructions for future reference. Read carefully before attempting to assemble, install, operate or maintain the product described. Protect yourself and others by observing all safety information. Failure to comply with these instructions will result in voiding of the product warranty and may result in personal injury and/or property damage.

General - Safety Information

Only qualified personnel should install this unit. Personnel should have a clear understanding of these instructions and should be aware of general safety precautions. Improper installation can result in electric shock, possible injury due to coming in contact with moving parts, as well as other potential hazards. If more information is needed, contact a licensed professional engineer before moving forward.

1. Follow all local electrical and safety codes, as well as the National Electrical Code (NEC), the National Fire Protection Association (NFPA), and the Canadian Electrical Code (CEC), where applicable.
2. Unit must be securely and adequately grounded.
3. Verify that the power source is compatible with the equipment.
4. Electrical equipment should be transported, stored, installed, and operated only in the environment for which it is designed.

DANGER

Improper installation, adjustment, alteration, service or maintenance can cause property damage, injury or death. Read the installation, operating and maintenance instructions thoroughly before installing or servicing this equipment.

WARNING

Always disconnect power before working on or near a unit. Use appropriate lockout tagout procedures to prevent accidental power up.

NOTICE

This appliance is not intended for use by persons (including children) with reduced physical, sensory or mental capabilities, or lack of experience and knowledge, unless they have been given supervision or instruction concerning use of the appliance by a person responsible for their safety. Children should be supervised to ensure that they do not play with the appliance.

Receiving Inspection and Hanging/Installation Requirements

Prior to removing the shipping materials, visually inspect the packing materials. There should be a black plastic strip wrapped in the clear plastic stretch wrap. If this black plastic strip is missing, the shipment may have been repacked by the shipper and you should make a note of this on the shipping documents and inform the delivering carrier. If any damage or other concerns are present, make a note of this on the shipping documents and inform the delivering carrier.

After unpacking the Single Duct Air Terminals, check for shipping damage. If any shipping damage is found, report it immediately to the delivering carrier.

Always store the product in a clean dry location prior to installation.

Units with controls are not recommended for use in ambient temperatures greater than 95°F. For protection of controls, do not store in temperatures above 135°F.

General - Model Number Code

The model number code provides basic identification of the unit.

Installation

CAUTION: HAZARD OF EQUIPMENT DAMAGE
Do not use the flow sensor, connecting tubing or damper shaft as a lift point. Damage to the components may result.

NOTICE: Unit is not recommended for installation above 2,000 m.

Unless local building codes require hangers, the smaller size basic Single Duct Air Terminals may be light enough to be supported by the ductwork itself. However, when accessory components such as controls, hot water reheat coils, sound attenuators or electric reheat are included, the single duct terminal should be supported directly with straps screwed into the side of the terminal. (See figure 1)

Figure 1 - Hanging Straps

Description of Figure 1: Illustrates metal strap-hangers secured to building structure, supporting the unit. Features include Air Flow Sensor, Compression strap on flexduct to ensure airtight joint, Basic Air Terminal, Damper Shaft, Slip & Drive Connections, Duct, Optional Hot Water Coil. Notes indicate minimum three equivalent (de) duct diameters of straight duct on air terminal inlet recommended, and a method for attaching the coil with a 1/2" long sheet metal screw.

Alternate trapeze hangers or the method prescribed for the rectangular duct on the job specification may be used. (See figure 2)

Figure 2 - Trapeze

Description of Figure 2: Depicts trapeze hangers. Features include Air Flow Sensor, Compression strap on flexduct to ensure airtight joint, Basic Air Terminal, Damper Shaft, Optional Sound Attenuator (SA), Duct. Notes indicate maintaining 10-1/2" clearance from air terminal to support rods for access to controls, 5/16" or 3/8" diameter hanger rods secured to building structure, and 3/4" x 3/4" x 1/8" angles for support.

Figure 3 - Optional Hanger Brackets and Hanger Rods

Description of Figure 3: Shows a diagram of a Single Duct Air Terminal with optional hanger brackets and hanger rods (5/16" minimum). Features include Primary air inlet and the main body of the terminal.

Single Duct Terminal Units are not designed nor suitable for outdoor use.

In advance of start-up, verify all electrical connections are tight and the correct voltage is supplied to the Single Duct Terminal Unit per the rated voltage listed on the unit label. If factory-supplied controls are present, review all wiring diagrams to assure a complete working knowledge.

IMPORTANT

If equipped with pneumatic controls, the orientation of the Single Duct Air Terminal unit is critical. The pneumatic controls must be mounted right side up. The Single Duct Terminal must be level within + or – 10 degrees of horizontal, both parallel to the airflow and at right angle of airflow. The control side of the Single Duct Terminal is labeled with an arrow indicating up. Unless otherwise noted, most electric, analog electronic and digital controls are not position sensitive and may be installed in any orientation.

MINIMUM CLEARANCE FOR ACCESS

Single Duct Air Terminals require sufficient space to allow servicing of the controls and electric reheat power hookup (if applicable). Horizontal clearance requirements are dependent upon access panel dimensions which are indicated on the appropriate submittal. For control panel access, a minimum of 18" is recommended. See the appropriate submittal for control panel location.

CAUTION
These clearance recommendations are not meant to preclude NEC requirements or local building codes that may be applicable, which are the responsibility of the installing contractor.

CONNECTING DUCT WORK

NOTICE: Do not insert duct work inside the inlet collar of the Single Duct Air Terminal. Inlet duct should be installed in accordance with SMACNA guidelines.

1. Slip each inlet duct over the inlet collar of the Single Duct Air Terminal.
2. Fasten and seal the connection by method prescribed by job specification.
3. The diameter of the inlet duct in inches must be equal to the listed size of the Single Duct Air Terminal; e.g., a duct that actually measures 8 inches must be fitted to a size 8-inch Single Duct Air Terminal. The inlet tube of the Single Duct Air Terminal is manufactured 1/8" smaller than the listed size in order to fit inside the duct.
4. If an inlet airflow sensor is installed, it is recommended the installer provide a minimum of 3 duct diameters of straight duct at the Single Duct Air Terminal inlet.
5. The outlet end of the Single Duct Air Terminal is designed for use with slip and drive duct connections (flanged outlets optional).
6. A rectangular duct the size of the Air Terminal outlet should be attached. (Refer to submittal for correct size.)

FIELD ELECTRICAL WIRING

DANGER
High voltage electrical supply is needed for this equipment. The control cabinet contains live electrical parts. Contacting these parts with power applied may cause serious injury or even death. This work should only be performed by a qualified electrician.

All field wiring must comply with local building codes and NEC. (ANSI/NFPA 70).

When applicable, electrical control and piping diagrams are attached to the inside of the control enclosure cover of the Single Duct Air Terminal.

Use copper only conductors with insulation rated 75°C.

The Single Duct Air Terminal must be properly grounded per NEC 424-14 and 250.

Always check product label for voltage and current data to determine the proper wire size and over current protection.

The control panel cover must be closed or in place before applying electric power to the Single Duct Air Terminal.

These recommendations are not meant to preclude NEC requirements or other applicable local building codes and are the sole responsibility of the installing contractor.

NOTICE: If the unit is not ordered with an internal disconnecting device then a disconnection device that shall disconnect all phases must be provided by the customer and incorporated in the fixed wiring.

SINGLE DUCT AIR TERMINALS WITH ELECTRICAL REHEAT

WARNING
Single Duct Air Terminals must not be operated without downstream ductwork in place. Failure to have downstream ductwork installed will expose the line voltages and high temperature present in the operating heater elements. Contact with these heater elements may cause serious injury or death.

• Prior to installation always inspect the electric heating coils for damage.
• All electric reheat is balanced by kW per stage.
• The installing electrician should rotate the electric reheat stages by phase in order to balance the buildings electrical load.
• The "UP" arrow orientation must be followed to prevent nuisance tripping or overheating which will cause damage to the electric heater and or building.

SINGLE DUCT AIR TERMINALS WITH HOT WATER COILS

CAUTION: HAZARD OF EQUIPMENT DAMAGE
The copper tubing should not be used as lift points. Always inspect the hot water coils for damage prior to installing the Single Duct Air Terminal.

• The hot water coil casing must be field insulated.
• The hot water coils do not have drip pans and are not suitable for use as cooling coils.
• The hot water coil maximum water operating temperature is 195°F.
• The hot water coils are leak tested to 300 psi, with a minimum burst pressure of 2000 psi at ambient temperature.

CONTROLS

NOTICE: Single Duct Air Terminals with digital controls, if factory programmed, incorporate specific communication addresses. Installing the Single Duct Air Terminal in a different location than noted on the Single Duct Air Terminal label and building plans may result in excessive start-up labor and is the sole responsibility of the contractor.

For information on controls provided by other manufacturers and installed on the Air Terminals, contact the local branch or dealer.

INLET FLOW SENSOR

Single Duct Air Terminals are shipped with factory-installed (where applicable) pressure differential inlet flow sensors in the primary inlet. See figure 4 for calibration curve and K factors. Bypass Air Terminals offer an optional downstream flow sensor for field installation a minimum of 3 feet downstream of box discharge.

Troubleshooting

Investigating Noise Complaints

• Noise from a Single Duct Air Terminal can be due to a variety of conditions and can be difficult to eliminate.
• The first step is to isolate the type, source and direction.
• Generally, noise heard at the air outlet is considered a discharge type.
• Noise heard through the ceiling is considered radiated noise.
• For detailed information concerning noise transmission in buildings, refer to AHRI Standard 885-2008, "Procedure for estimating occupied space sound levels in the application of air terminals and air outlets".

Discharge Noise

• This is usually caused by high static pressure or little to no internal duct lining downstream of the Air Terminal.
• It can sometimes be caused by the air outlet itself.
• Air outlet generated sounds can be reduced by reducing flow or increasing an outlet size.
• Reducing static pressure, flow or adding additional downstream attenuation materials will reduce discharge sounds from the Air Terminal.

Radiated Noise

• Radiated noise is most commonly associated with Fan Powered Terminals.

Electric Duct Heater

CAUTION
Use extreme care if testing the electric heater with power on. The control cabinet contains live electrical parts. Contacting these parts with the power applied may cause serious injury or death. This unit should be serviced by a licensed electrician or a similarly qualified electrical service technician.

If the electric heater does not operate:

• Check electric power into the unit and verify the input power agrees with the label data.
• Verify the Air Terminal is installed properly (according to the airflow orientation).
• Review the wiring diagram attached to the inside of the control enclosure cover to verify the field wiring is correct with proper gauge wire, overcurrent protection and properly grounded.

If the electric heater cycles on and off:

• Verify the airflow is uniformly distributed across the face of the heater elements.
• Check for obstructions in the duct or insufficient airflow. (70 cfm per kW required)

If conditioned space fails to warm up:

• Verify the electric heater controls and thermostat are compatible and wired properly.
• Relocate the room thermostat if it is located in a position that is too warm.

If condition space overheats:

• Verify the electric heater controls and room thermostat are compatible and wired properly.
• Relocate the room thermostat if it is located in a position that is too cold.
• Verify the air distribution to the space is appropriate for the required thermal load.

Specific Electric Heater Troubleshooting Procedures: PROBLEM: Heater Does Not Energize

Specific Electric Heater Troubleshooting Procedures: PROBLEM: Heater Does Not Energize

WARNING
On all troubleshooting that requires working inside the heater casing, disconnect the power first! Jumpers used for diagnostic purposes should be removed before returning the heater to normal operation.

Figure 4 - Multi-Quadrant Averaging Flow Sensor

This section details the Multi-Quadrant Averaging Flow Sensor, including model compatibility, inlet sizes, and K-factors. The K-factor is defined as the calibration flow constant at 1 in. wg delta P.

Shape Dimensions:

Round:

Flat Oval:

Rectangle:

Formula: Cfm = √Δp x K Factor

Description of Graph: "Logarithmic Flow Rate vs Pressure Drop" shows multiple lines representing different models/sizes, plotting Flow Rate (cfm) on the x-axis against Sensor AP (in. wg) on the y-axis (logarithmic scale).

Our Commitment

As a result of our commitment to continuous improvement, Greenheck reserves the right to change specifications without notice.

Product warranties can be found online at Greenheck.com, either on the specific product page or in the literature section of the website at Greenheck.com/Resources/Library/Literature.