Trane ZN520, Tracer Unit Ventilator User Manual

Installation

Owner

Diagnostics

Tracer® ZN.520 for Classroom

Unit Ventilator

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Start-up Procedures

Installation of New Units

1.Follow all instruction for installation of classroom unit

ventilators as detailed in UV- IOM-1 (Installation Operation Maintenance manual).

2.Disconnect power or disable the circuit breaker to unit.

3.Run communication link wire when required. (See wiring diagram in the unit).

4.Install zone sensor when

required. (See wiring diagram in the unit and zone sensor submittals).

5.Reapply power.

6.Check for GREEN Status LED

operation to ensure power has been made to the TracerTM ZN.520 unit controller.

7.Check for YELLOW Comm LED

operation to help ensure communication has been made to the Tracer ZN.520 unit controller when required.

Peel IDENTIFICATION TAG from

unit and place in the Appendix of this document, or on building plans for future location use. The

actual room location on the tag may be hand written.

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Start-up Procedures

Power Up Sequence

Manual output test can be initiated

at any time in the power up sequence or during normal operation.

When 24 VAC power is initially applied to the controller, the follow-

ing sequence occurs:

1.Green Status LED turns on.

2.All outputs are controlled Off.

3.The controller reads input values to determine initial values.

4.Standalone control is assumed unless occupancy data is communicated.

5.Random start timer expires (5 to 30 seconds, random).

6.Power-up control Wait feature is applied. When power up

control Wait is enabled, the controller waits 120 seconds to allow ample time for commu-

nicated control data to arrive. If, after 120 seconds, the controller does not receive a com-

municated occupancy request, the unit assumes standalone operation.

7.All modulating valves and

damper calibrate closed, face and bypass damper calibrate to bypass (when present).

8.Normal operation begins after

290 (potentially) seconds have passed.

Note: Manual output test can be initiated at any time.

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General Information

Tracer® ZN.520

Overview

The Trane® Tracer® ZN.520 controller is a factory-installed and

commissioned, direct-digital controller (DDC) offering for classroom unit ventilator sys-

tems. (See Figure 1: “Tracer ZN.520 Control Board”) The Tracer ZN.520 can also be applied to

other Trane® interoperable HVAC equipment, including the fan coil and blower coil products. (For

more information see,Table 1: Tracer™ ZN.520 Unit Controller features and coil availability, on

page 8 for more information.) For more information regarding the application of the Tracer ZN.520

to other Trane products, contact the appropriate local Trane sales office.

Trane offers a complete solution to space comfort control with the

flexibility of Integrated Comfort System (ICS) and stand-alone control packages. The ICS control

package combines HVAC equipment and building management into one environmental comfort

system.

Integrating the Tracer ZN.520 on

classroom unit ventilators, and tying them to a Tracer Summit® system will provide a complete

building management system. The stand-alone control package offers the features and function-

ality of the direct digital control without a front-end building automation system, while providing

future considerations for ICS.

Equipment problems can often be

diagnosed on each unit without having to access the unit componets. These diagnostics can be re-

ceived remotely via a modem with a Tracer Summit building automation system, thus reducing the

number of actual on-site service calls; through the Rover® service tool connected to a communica-

tion jack located inside the Trace zone sensor; or connected to the unit.

Figure 1: Tracer ZN.520 Control Board

The Tracer ZN.520 is factorymounted, tested, wired, config-

ured and commissioned for the selected application.

The Tracer ZN.520 configuration has flexible point and product configurations. For example, with

point configuration, a specific binary point can be configured to accept input from either a time clock

or some type of generic device.

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General Information

	Table 1: Tracer™ ZN.520 Unit Controller features and coil availability
				Auto	Face and				Entering
		Multiple	Dehumid-			Valve	Economizer	Auxiliary	Water
	Coil			Damper	Bypass
		Fan Speeds	ification			Control	Damper	Heat2	Temperature
				Adjust	Damper
									Sampling
	2-pipe changeover	X		X	X	X	X	X	X
	2-pipe hot water	X		X	X	X	X	X
	only
	2-pipe steam only	X		X	X		X	X
	2-pipe changeover/	X	X	X		X	X	X	X
	electric heat
	2-pipe cool only	X		X		X	X
	2-pipe cool only/	X1		X1		X	X	X
	electric heat
	4-pipe hot water/	X	X	X	X3	X	X	X
	chilled water
	4-pipe changeover	X	X	X	X3	X	X	X	X
	4-pipe steam/chilled	X		X		X	X	X
	water
	Electric heat only						X	X
	DX/hot water	X1		X1		X	X	X
	DX/steam	X1		X1		X	X	X
	DX/electric heat						X	X
	DX cooling only						X

1.Multiple fan speeds are available in hydronic units only.

2.Auxiliary heat is designed to bring on baseboard heat as the second stage of heating. The baseboard heat must be the same type as the

unit heating coil.

3. Units with face bypass dampers cannot actively dehumidify.

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Controller Circuit Board

Features

Power

Generic

Auto Test Button

Status LED

Communications LED

Service Button and LED

Communications	Zone Sensor Connections

Figure 2: Tracer ZN.520 unit controller circuit board

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Controller Features

Each Tracer ZN.520 unit controller circuit board is equipped with enhancements to help facilitate ser-

vice, testing, and diagnosis. Each board has

qManual test button,

qStatus LED,

qCommunication status LED,

qService button,

qQuick terminal connectors, and

qEasy to read screen printing.

(See Figure 1: “Tracer ZN.520 Control Board”).

Service

The Trane Tracer ZN.520 unit con-

troller is serviced using Rover®, the ICS software service too. Rover is designed to support the Tracer

ZN.520 unit controller on the classroom unit ventilator.

For “remote” access to the communicating units, the zone sensors offered with the Tracer ZN.520

have a telephone style (RJ-11) connector allowing field connection between Rover and the zone sen-

sor; however, the RJ-11 connector must be connected to the terminals TB2-5 and TB2-6 on the Tracer

ZN.520 unit controller.(See Figure 3: “Rover service tool connected to the RJ-11 communication jack in a

zone sensor”)

The zone sensor may also be used when trying to locate a unit. By pressing the ON button on the zone

sensor for 5 seconds or using the “wink” command in Rover, the circuit board receives the signal caus-

ing the Communication LED to “wink”. Winking allows visual identifier on the board for service

technicians.

The Tracer ZN.520 also includes

features such as a test output to manually test all of the end devices and color coded wires (i.e. red for

heating valves and blue for cooling valves) to aid in the troubleshooting process.(See “Manual Output

Test” on page 48, for more information.)

Figure 3: Rover service tool connected to the RJ-11 communication jack in a zone sensor

Typical Components

A typical classroom unit ventilator

system with a DDC package consists of the following physical components, in addition to the

mechanical equipment:

qTracer ZN.520—contains the

sensor input circuits, service adjustments, microprocessor control electronics, and communications hardware.

Power is supplied by a separately mounted 24 VAC\90 VA transformer.

qSensor Modules—a variety of analog sensors that provide

temperature and optional

humidity sensing and CO2 sensor; and an operator interface to the Tracer ZN.520 for operating modes, status, and temperature setpoints.

qStandard End Devices—a variety of devices that help to gather information, control

capacity, and provide ventilation are used by the Tracer ZN.520 in its control

algorithm to condition the space to the desired temperature and relative

humidity level. (See “Standard End Devices” on page13, for more information.)

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Communication Configurations

Note: The Tracer ZN.520 is a	connect to a maximum of 120
configured controller. It will	Tracer ZN.520 controllers.
not operate without a valid
downloaded configuration
file.
The Tracer ZN.520 controller sup-
ports ICS and peer-to-peer com-
munications as well as stand-
alone operation. A number of con-
trol features may be configured at
the factory or by using the Rover
service tool. (See “Configuration”
on page32, for more information.)

Integrated Comfort

System

Note: The Tracer ZN.520

controller may only be used with Tracer Summit version 11.0 or greater with a Comm5

communications card.

Classroom unit ventilators can op-

erate as part of a large building automation system controlled by Tracer Summit. The Tracer ZN.520

is linked directly to the Tracer Summit via a twisted pair communication wire. Each Tracer Summit

building automation system can

Figure 4: Communications link wire

The ICS system allows for complete communication with the classroom unit ventilators via

Tracer ZN.520 unit controller. All points connected to the Tracer ZN.520 may be observed from the

Tracer Summit front-end controller. The Tracer Summit can also initiate an alarm on a loss of per-

formance or equipment malfunctions.

The ICS system also allows all of

the classroom unit ventilators to share information without the presence of hardwired sensors at

each unit. Some typical shared points include outside air temperature, entering water temperature,

and occupancy schedules.

Peer-to-Peer

Communications

On a peer-to-peer communication

system, multiple Tracer ZN.520 controllers may share data, via a twisted pair communication wire,

without the need for a Tracer Summit system. (See Figure 5: “Peer- to-peer communication connec-

tions”)

Peer-to-peer communications al-

lows features such as master/slave operation, in which multiple units operate off of a single zone sensor.

This is typically seen in large spaces requiring multiple units.

The Rover service tool is required to set up peer-to-peer communications.

Figure 5: Peer-to-peer communication connections

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Communication Configurations

Stand-Alone

In a stand-alone configuration,

commands for operation are determined based on input from the zone sensor, humidity sensor, and

factoryor field-mounted timeclock.(See Figure 6: “Typical classroom unit ventilator installation”)

qThe timeclock is wired to the Tracer ZN.520 to index the unit

between occupied and unoccupied modes.

qA unit-mounted, analog, outside-air temperature sensor is used to initiate the dry bulb

economizer and freeze avoidance routines.

qOn changeover units, a unitmounted, analog, entering water temperature sensor is

used to automatically control the system in the heat/cool mode.

These sensors are required for proper system operation and are

provided as standard on standalone units.

Figure 6: Typical classroom unit ventilator installation

Communication Interface

Important! To help ensure

optimal performance of the Rover service tool, please use the latest version. To obtain

the latest version contact your local Trane sales representtative or service technician.

Note: Refer to the Tracer system manuals for more

information on communications.

The Tracer ZN.520 communicates via Comm5 (LonTalk) to a building management system, the Rover

service tool, and other unit controllers on the communications link. Each Tracer ZN.520 requires a

unique address for the system to operate properly. Every Tracer ZN.520 has this address (Neuron

ID) embedded in the microprocessor, which eliminates the need for field-addressing of the units. Each

unit also ships from the factory with a unit identification tag. (See “Location Identifier” on page38,

for more information.)

Building automation system

Trane offers a state-of the art frontend building automation system designed to coordinate and moni-

tor Trane equipment and controllers: Tracer Summit.

The Tracer Summit system allows the user to monitor and/or change Tracer ZN.520:

qstatus, parameters, sensor data, diagnostics, and internal variables; and

qsetpoints, operating modes, and outputs.

Service tool

Trane also offers a service tool to work in conjunction with the Tracer Summit system or with peer-to-

peer and stand-alone systems: the Rover service tool.

Communication to the Tracer ZN.520, or multiple controllers, can also be accomplished by using the

ICS software service tool.

A personal computer running Rover may be directly connected to a standalone Tracer ZN.520; con-

nected to the communications jack in the Trane zone sensor; or connected to a communicating unit’s

Tracer ZN.520 unit controller, to access all of the units on a communicating link.

Rover allows the user to interface with the Tracer ZN.520, but will not

allow any advanced control (e.g. equipment scheduling or trending). To purchase a copy of the ICS

software service tool, contact the BAS department at your local Trane dealer.

Interoperability

Trane has lead the industry with BACnet interoperability and Trane

is now expanding the realm of interoperable solutions by offering LonMark certified unit controllers.

The Tracer ZN.520 controller conforms to the LonMark Space Comfort Controller profile. (See

“Appendix—Data Lists” on page64, for more information.)

This allows the ZN.520 to be used

as a unit controller on other control systems that support LonTalk and the SCC profile. Now building own-

ers have more choices and design engineers have more flexibility to meet the challenges of building au-

tomation.

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Standard End Devices

Table 2: End Device Specifications

Device

Fan Status Switch

Low Temperature Detection Switch (Freezestat)

OutsideAir Sensor/discharge AirSensor/Entering

Water Temperature Sensor/Unit Mounted, Zone

Return-air Temperature Sensor

Characteristic

Material

Operating Temperature Range

Contact Form

Preset

Trip Temperature:

Release Temperature

Rating—Auto Reset

Sensing Element

Description

Contact Blade—Pilot duty rated

-40°F/250°F (-40°C/120°C)

SPST-NO

Fan status - 0.07”

36°F ± 2°F (2°C + - 1.11°C)

44°F ± 3°F (6.67°C + - 1.67°C)

	Pilot Duty	120	VAC	240	VAC
	(24 VAC)
	FLA	10.0		5.0
	LRA	60.0		30.0

Thermistor 10 KOhms @ 77°F ± 1.8°F (25°C ±1°C)

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Standard End Devices

Table 2: End Device Specifications
Device	Characteristic	Description
Outside Air Actuator	Description	Three-point floating with spring return
	Ambient Temperature Rating	-25°F to 125°F
	Power Consumption	5 VA
	Torque	35 in-lbs.

Drive Time

90 seconds, 95 degree stroke

Face and Bypass Actuator	Description	Three-point floating
	Ambient Temperature Rating	32°F to 122°F
	Power Consumption	3 VA
	Torque	35 in-lbs.

Drive Time

80-110 seconds, 95 degree stroke

2-way Control Valve	Description	Three-point modulating
	Ambient Temperature Rating	140°F at 95% relative humidity
	Drive Time	50 seconds
	Max Pressure	400 psi water
	Close Off	Varied by size and Cv

Temperature

Water 200°F maximum

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Standard End Devices

Table 2: End Device Specifications
Device	Characteristic	Description
3-way Control Valve	Description	Three-point modulating
	Ambient Temperature Rating	140°F at 95% relative humidity
	Drive Time	50 seconds
	Max Pressure	400 psi water
	Close Off	Varied by size and Cv

Temperature

Water 200°F maximum

Time clock	Size	2.83'' x 4.0'' x 2.06''
	Power Consumption	4.4 VA
	Switch	SPDT dry contacts, silver cadmium oxide
	Switch Rating	16A 250V resistive, 1000 Watts tungsten
	Minimum Switching Current	100mA,230V
	Shortest Switching Time	1 minute
	Ambient Temperature Range	-14°F to 131°F
	Wiring Connections	Screw terminals suitable for #10 to #24 AWG
	Backup	Seven day capacitor backup
Zone sensor

	Zone Sensor Wiring Size And	16-22 AWG: up to 200 feet
	Maximum Lengths

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Standard End Devices

Table 2: End Device Specifications
Device	Characteristic	Description
Humidity Sensor	Sensing Element	Polymer capacitive
	Sensing Element	Accuracy: ± 5% over 20-95% RH @ 77ºF
	Range	0 to 99% RH
	Operating Temperature Range	0°F to 140ºF
	Max Supply Voltage	24VDC
	Output Characteristics	4 to 20 MA for 0-100% RH
	Drift Rate	Less than 1% per year
CO 2 Sensor	Sensing Element	Accuracy: ± 100ppm full scale
	Range	0-2000 ppm
	Operating Temperature Range	59°F to 95ºF
	Supply Voltage	24VAC
	Output Characteristics	0-10 VDC for 0-2000 ppm
	Power consumption	10 VA
	Drift Rate	±5% full scale over four years
Fan Relay		20 amps at 120/240 vac
		3/4 hp at 120 vac
	Contact Rating	1 1/2 hp at 240 vac
		20 amps @ 28 vdc
		DPDT
	Terminals	0.25 quick connect
	Contact material	Silver-Cadium Oxide
	Coil	24 vac 2.7 va

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Standard End Devices

Table 2: End Device Specifications
Device	Characteristic	Description
	Type	N.E.C. Class 2
	Primary Voltage	120 vac
Control Transformer		24 vac at 90 va
	Secondary voltage	Manual reset
		4amp fuse in 24-volt circuit

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Installation and Wiring

Specifications

Dimensions

Tracer ZN.520 board and mounting hardware:

•Height: 5.25 inches (133 mm.)

•Width: 5.50 inches (140 mm)

•Depth: 2.25 inches (57 mm)

Power Requirements

•18 to 32 VAC (24 VAC nominal)

•50 or 60 Hz

•570 mA AC

Operating Environment

•32° to 140°F (0× to 60°C)

•5% to 95% relative humidity, non-condensing

Storage Environment

•-40° to 185°F (-40° to 85°C)

•5% to 95% relative humidity, non-condensing

Agency Listings

•UL and CUL 916 Energy Management System

•Agency Compliance IEC 1000- 4-2 (ESD), IEC 1000-4-4(EFT), IEC 1000-4-5 (Surge)

Figure 7: Tracer ZN.520 circuit board schematic

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Installation and Wiring

Binary Inputs

Each binary input associates an input signal of 0 VAC with open con-

tacts and 24 VAC with closed contacts.

Table 3: Binary inputs (typically 24 mA AC)

	Description	Terminals	Terminal Function
	Binary input 1	J2-1	24 VAC
	(BI 1)
		J2-2	Input
	Binary input 2	J2-3	24 VAC
	(BI 2)
		J2-4	Input
	Binary input 3	J2-5	24 VAC
	(BI 3)
		J2-6	Input
	Binary input 4	J2-7	24 VAC
	(BI 4)
		J2-8	Input

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Installation and Wiring

Binary Outputs

Outputs are load side switching tri-

acs. The triac acts as a switch, either making or breaking the circuit between the load (valve, damper,

contactor, relay) and ground.

Table 4: Binary outputs

Description

Fan high

Fan medium,

Exhaust fan

Fan low

No connection

Cool open, face bypass cool valve DX, 2-position cooling valve, BI 5

Cool close

Face/bypass damper open

Face/bypass damper close

Heat open

Face bypass isolation valve, 2-position heating valve Electric heat 1st stage

Heat close

Electric heat 2nd stage

Economizer damper open

Economizer damper close

	Terminals	Output
		Rating
	J1-1	12 VA
	J1-2	12 VA
	J1-3	12 VA
	J1-4 (Key)	—
	J1-5	12 VA
	J1-6	12 VA
	J1-7	12 VA
	J1-8	12 VA
	J1-9	12 VA
	J1-10	12 VA
	J1-11	12 VA
	J1-12	12 VA

Load Energized	Load De-energized
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)
—	—
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)
1 VAC RMS	24 VAC RMS
(typical)	(typical)

Generic/baseboard Heat Binary Output

Table 5: Generic binary outputs
Description	Terminals	Output	Load Energized	Load De-energized
		Rating
Generic/ baseboard heat output	TB4-1	12 VA	1 VAC RMS	24 VAC RMS
			(typical)	(typical)
24VAC	TB4-2	12 VA	NA	NA

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Installation and Wiring

Analog Inputs

Table 6: Analog inputs
Description	Terminals	Function	Range
Zone	TB3-1	Space temperature input	5° to 122°F
			(-15° to 50°C)
Ground	TB3-2	Analog ground	NA
Set	TB3-3	Setpoint input	40 ° to 115 °F
			(4.4° to 46.1°C)
Fan	TB3-4	Fan switch input	4821 to 4919 Ω (Off)
			2297 to 2342 Ω (Auto)
			10593 to 10807 Ω (Low)
			13177 to 13443 Ω (Medium)
			15137 to 16463 Ω (High)
Ground	TB3-6	Analog ground	NA
Analog Input 1	J3-1	Entering water temperature	-40° to 212°F (-40° to 100° C)
	J3-2	Analog ground	NA
Analog Input 2	J3-3	Discharge air temperature	-40° to 212°F (-40° to 100° C)
	J3-4	Analog ground	NA
Analog Input 3	J3-5	Outdoor air temperature / Generic	-40° to 212°F (-40° to 100° C)
		temperature
	J3-6	Analog ground	NA
Analog Input 4	J3-7	Power port	4-20 mA
	J3-8	Universal input
		Generic 4-20ma	0 – 100%
		Humidity	0 – 100%
		CO2	0 – 2000ppm
	J3-9	Analog ground	NA

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Installation and Wiring

Mounting

The Tracer ZN.520 circuit board is

mounted in the left-hand end pocket for all classroom unit ventilator configurations. The sheet metal

mounting plate has raised embosses to accept the mounting feet on the circuit board. (See Figure 8:

“Classroom unit ventilator control box with close-up of horseshoe embosses and circuit board

mounting feet.”) This design allows the Tracer ZN.520 controller to be secured with a minimal num-

ber of sheet metal screws.

Figure 8: Classroom unit ventilator control box with close-up of horseshoe embosses and circuit board mounting feet.

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Installation and Wiring

The mounting position on the ver-

tical classroom unit ventilator configuration allows complete access to the Tracer ZN.520 by re-

moving the front panel. (See Figure 9: “Vertical classroom unit ventilator end pocket”) The

mounting plate swings out of the way with the removal of a single screw to allow access to the com-

ponents behind the control board.

The mounting plate on the hori-

zontal classroom unit ventilator configuration is designed to slide out with the removal of a sin-

gle screw for complete access to the Tracer ZN.520. (See Figure 10: “Horizontal classroom unit venti-

lator end pocket”) The location of the control board on this unit configuration allows complete access

to the other components in the end pocket when the front panel is removed.

For additional convenience, quick

connects and modular wire harnesses are used on the control board and mounting plate. (See

Figure 11: “Quick connects to control board in the classroom unit ventilator”) These quick connects

help facilitate ease of wiring devices (e.g., zone sensor) to the control board, and helps add accessibility

to major components.

Figure 11: Quick connects to control board in the classroom unit ventilator

Figure 9: Vertical classroom unit ventilator end pocket

Figure 10: Horizontal classroom unit ventilator end pocket

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Installation and Wiring

Wiring

! WARNING

Warning! Disconnect all electrical power before servicing unit to prevent injury or death due to electrical shock. Use copper conductors only. The use of aluminum or other incorrect types of wire may result in overheating and equipment damage.

! CAUTION

Caution: To prevent damage to the unit ventilator, refer to the diagram provided on the inside of the unit's access panel for specific wiring infor-

mation. All controls are wired at the factory. Single point power, zone sensor, and communication wiring is to be installed by the contractor.

Important! All wiring must comply with state, local, and federal guidelines. Contact the

appropriate local agency for furthur information.

Important! Wires for temperature sensors, communication lines, 24 VAC,

and contact closure sensing inputs should not be bundled with or run near high voltage

wiring.

qPower wiring must be

separated from the Tracer ZN.520 and all low voltage wires. External input wires

should be run in separate conduits from high voltage wires.

qWires connected to pin headers should be formed and routed

so as to cause minimum strain on the Tracer ZN.520 connector.

qA minimum of 1.5" clearance (from the pin centerline) for wires up to 16 AWG is

recommended for bending and forming wires.

qAll sensor and input circuits are at or near ground potential. Do not connect any sensor or input

circuit to an external ground connection.

qA close-coupled ground connection is required for the Tracer ZN.520. T

qTable 7: Tracer ZN.520 Wiring Requirements, shows Tracer ZN.520 wire types and lengths.

Table 7: Tracer ZN.520 Wiring

Requirements

	Application	Wire Type	Length
	Contact Closure	18 AWG	Up to
			1000 ft.
	24 VAC	16-22 AWG	Up to
			1000 ft.
	Thermostat	16-22 AWG	Up to
			1000 ft.
	Zone	16-22 AWG	Up to
	Sensor		200 ft.
	Communications	Belden 8760	Up to
		or equivalent	5000 ft.

Power

The Tracer ZN.520 controller is

powered by 24 VAC. (See Table 7: “Tracer ZN.520 Wiring Requirements”)A total of two 1/4-inch

quick-connect terminals are provided for 24 VAC connection to the board.

Figure 12: Power connection to the Tracer ZN.520 unit controller

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Installation and Wiring

Installing the WallMounted Zone Sensor (Optional)

Zone sensor location is an important element of effective room

control and comfort.

The best sensor location is typical-

ly on a wall, remote from the HVAC unit. Readings at this location assure that the desired set-

point is achieved across the space, not just near the unit itself.

Note: It may be necessary to

subdivide the zone with multiple units to ensure adequate control and comfort

throughout the space.

The following are typical areas

where the zone sensor should NOT be mounted:

qNear drafts or “dead spots” (e.g., behind doors or corners);

qNear hot or cold air ducts;

qNear radiant heat (e.g., heat

emitted from appliances or the sun);

qNear concealed pipes or chimneys;

qOn outside walls or other nonconditioned surfaces; or

qIn air flows from adjacent zones or other units.

Figure 13: Proper zone sensor placement

Note: All zone sensor wiring

will be done in the factory unless zone sensor options are selected to be wall mounted.

When a unit-mounted speed switch is selected with a wall-

mounted zone sensor, the contractor must disconnect the cooling setpoint on the unit mounted sen-

sor if the wall mounted cooling setpoint is used. The zone signal will be cut at the factory. The unit-

mounted speed switch cannot be used as a zone sensor.

THe communications link is not connected in the factory. Communications should be wired to the

wall-mounted sensor.

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Installation and Wiring

Humidity and CO2 Sensors

Humidity and CO2 sensors should be mounted in a similar location as the zone sensor.

Figure 14: Relative humidity sensor

Figure 15: CO 2 Sensor

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Typical Wiring Diagram—Wall

Mounted Zone Sensor

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