Greenheck IGX Installation Manual

Part #474681

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Packaged DX Module

Installation, Operation and Maintenance Manual

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 instructions could result in personal injury and/or property damage!

As used in Greenheck models

•DGX

•IGX

•MSX

Recognized Component

General Safety Information

Only qualified personnel should install and maintain this
system. 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. Other
considerations may be required if high winds or seismic
activity are present. 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 Agency (NFPA), where applicable.
Follow the Canadian Electric Code (CEC) in
Canada.

2. Unit must be securely and adequately grounded.

3. Verify that the power source is compatible with
the equipment.

4. Never open access doors to the unit while it is
running.

DANGER

• Always disconnect power before working on or
near this equipment. Lock and tag the disconnect
switch or breaker to prevent accidental power up.

• If this unit is equipped with optional gas

accessories, turn off gas supply whenever power
is disconnected.

CAUTION

This unit is equipped with a compressed refrigerant

system. If a leak in the system should occur,
immediately evacuate and ventilate the area. An
EPA Certified Technician must be engaged to make
repairs or corrections. Refrigerant leaks may also

cause bodily harm.

CAUTION

When servicing the unit, the internal components

may be hot enough to cause pain or injury. Allow

time for cooling before servicing.

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Packaged DX Module for Make-Up Air

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Receiving

This module is installed as a component of a make­up air unit and does not require any special handling.
Refer to the Receiving portion of the unit Installation,
Operation and Maintenance (IOM) Manual for complete
instructions on receiving, unpacking and handling.

Unpacking

The unit is shipped as a complete installed unit.
Protective coverings have been installed on the face
of the condenser coil that should be left in place until
installation of the unit is complete. The only item
that was shipped loose with the unit is the P Trap kit.
Verify that the P Trap kit has been received. Refer to
Unpacking instructions in unit IOM.

Handling

Units are to be rigged and moved by the lifting brackets
provided. Do not forklift. Refer to the Handling portion of
the unit IOM for complete instructions on handling.

Storage

Units are protected against damage during shipment. If
the unit cannot be installed and operated immediately,
precautions need to be taken to prevent deterioration of
the unit during storage. The user assumes responsibility
of the unit and accessories during storage. The
manufacturer will not be responsible for damage during
storage. The following suggestions are provided solely
as a convenience to the user.

Inspection and Maintenance During
Storage

While in storage, inspect units once per month. Keep
a record of inspection and maintenance performed. If
moisture or dirt accumulations are found on the parts,
the source should be located and eliminated. At each
inspection, rotate all moving parts by hand ten to
fifteen revolutions to distribute lubricant on motor and
bearings. If paint deterioration begins, consideration
should be given to touch-up or repainting. Units with
special coatings may require special techniques for
touch-up or repair.

Machined parts coated with rust preventative should
be restored to good condition promptly if signs of rust
occur. Immediately remove the original rust preventative
coating with petroleum solvent and clean with lint-free
cloths. Polish any remaining rust from the surface with
crocus cloth or fine emery paper and oil. Do not destroy
the continuity of the surfaces. Wipe clean thoroughly
with Tectyl® 506 (Ashland, Inc.) or the equivalent. For
hard to reach internal surfaces or for occasional use,
consider using Tectyl® 511M Rust Preventative or
WD-40® or the equivalent.

Table of Contents

General Safety Information ...................1

Receiving, Handling, Storage .................2

Product Overview ...........................2

Subassemblies ..............................3

Coils .....................................3

Dampers ..................................3

DX System ................................3

Installation

Service Clearances ..........................4

Additional Clearances for Packaged DX Units ....4

Lifting ....................................4

Condensate Drain (P Trap) ....................4

Switch S4 .................................4

Component Operation

Compressor Components ....................5

Electrical Components .......................5

Refrigerant Components .....................5

Additional Control Components ...............5

Factory Installed Refrigeration System

Components ...............................6

Sequence of Operation

Control Sequence ...........................7

Optional Variable Air Volume ..................7

Start-Up Unit

Model and Serial Number ....................8

Pre-Start-Up Checklist .......................9

Special Tools Required ......................9

Voltage Imbalance ..........................9

Start-Up Checklist .........................10

Troubleshooting

Refrigeration Circuit .....................11-14

Routine Maintenance

Monthly ..................................15

Annually .................................15

Maintenance Procedures ....................15

Reference

Component Location .......................15

Maintenance Log ....................Backcover

Warranty ...........................Backcover

Packaged DX Module for Make-Up Air Unit

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Product Overview

Subassemblies:

The Packaged DX Module for make-up air is a
horizontally configured unit that is installed as a
package in make-up air units and is designed for
outdoor installations. The Packaged DX Module is used
to temper the air that is supplied to the building. The
make-up air unit is designed to provide sufficient air to
replace air that is exhausted from the building and this
module is designed to provide necessary cooling.

The DX system comes fully charged with R-410A
refrigerant from the factory and is ready for operation
upon arrival.

Units may be supplied with one or two compressors
based on required cooling capacity. All units with
multiple compressors allow for staging of compressors
to meet a wider range of outdoor air loads while
reducing the number of cycles per compressor.

Compressed Refrigerant

All packaged DX modules are charged with
environmentally friendly R-410A compressed refrigerant.
Do not use tools or parts designed for other refrigerants
on this unit.

Safety Listing

Make-up air units are listed per ANSI/UL 1995, Heating
and Cooling Equipment and are ETL Certified.

Supplemental Installation, Operation and
Maintenance Manuals

Refer to the Installation, Operation and Maintenance
manual for the Make-Up Air unit for additional
information.

Coils

Every module is supplied with a single DX evaporator
coil. If there is only one cooling circuit, then the DX coil
is not divided. If two cooling circuits are specified, then
the DX coil will be a split-face. A single condenser coil is
attached to the exterior of the module. If more than one
cooling circuit is present, that condenser coil will be of
split-face configuration.

Dampers

Only an inlet damper may be installed in a PDX module
and it will only be found when the module is installed in
either model IGX or MSX that was not ordered with an
inlet damper module.

DX System

The DX system in the module is a complete, sealed unit
with compressed R-410A refrigerant. It consists of one
or two compressors, evaporator and condenser coils
and the following integral components:

• expansion valves

• liquid line lter-drier

• service / charging valves

• moisture indicating sight glass

• crankcase heater on each compressor

Each DX system incorporates the following:

• high pressure manual reset cutout

• low pressure auto-reset cutout

Models and Capacities

The Packaged DX Module for Make-Up Air Units is
manufactured in three different platform sizes, each
of which has several
different output tonnage
options. Examine
shipping documents to
verify correct model of
the module as received.

Platform Tonnage

H12 3, 5, 6, 8

H22 7, 9, 10

H32 10, 12, 16

Model Number

A metal plate is located on the fixed panel access to the
control center. The plate is marked with the Platform
Type and Tonnage (for example, H12-6). Record the
model number here:

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Packaged DX Module for Make-Up Air Unit

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Installation

Service Clearances

All make-up air units require minimum clearances on all
sides for routine maintenance. Filter replacement, drain
pan inspection and cleaning, fan bearing lubrication and
belt adjustment are all examples of routine maintenance
that must be performed. Blower and motor assemblies
and coil and filter sections are always provided with a
service door or panel for proper component access.
Clearances for component removal may be greater than
the service clearances. Refer to submittal drawings for
these clearance dimensions. See also Page 4 of this
manual.

Additional Clearances for Packaged DX
Units

Packaged DX units require additional service clearance
because they must have unrestricted air movement
around the condenser coil and condenser fans. Hot air
is being discharged from the condenser fans during
operation and the more clearance available, the better
the chance of avoiding recirculation or coil starvation.
This unit should never be placed under an overhang or
inside a building. A minimum of 48 inches above the
condenser fans is recommended.

Lifting

All units equipped with this module are provided with
either four or six lifting lugs. When the unit is being
hoisted, all of the provided lugs must be used for
support. Four lifting lugs are on the four corners of
the unit, located at the base. In addition, there may be
two more lifting lugs located at the top of the unit. The
locations of those two top lugs varies somewhat from
unit to unit.

Use spreader bars as shown to prevent damage to the
cabinet. If top-mounted lifting lugs are present, they
must be used in conjunction with the bottom-mounted
lifting lugs when hoisting the unit.

Minimum 48 inches clearance

Condenser Fans

End view of make-up air unit

with Packaged DX

Condenser Fans

and

Condenser Coil

Outdoor

48 inches clearance

Air Intake

42 inches clearance

42 inches clearance

Minimum 42 inches

clearance

Condenser Coil

Indirect Gas-Fired

Furnace

Unit Control Center

Use lifting lugs on

all four corners.

Lifting Details

Install Condensate Drain (P Trap)

The only installation step that
is specific to the DX module is
installation and priming of the
engineered P trap. Locate the
P trap kit that was shipped with
the unit and install the kit in
accordance with the enclosed
instructions.

Provide and Install Switch S4

Each Packaged DX unit requires an On/Off switch to
enable the unit to run. This is a user-supplied switch
that may be a toggle switch mounted in a 2 x 4 inch
electric box (mounted in a position chosen by the user),
or it may be a simple jumper or even a control switch
installed in a remote control panel supplied by the
factory. See also “Additional Control Components” on
page 5 of this manual.

36 inches clearance

Packaged DX Module for Make-Up Air Unit

4

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Component Operation

Compressor Components

Each Packaged DX module has a complete set of
compressor contactors, condenser fan contactors,
relays and certain integral safety controls located in the
module.

Typical Packaged DX Compressor Compartment

Electrical Components

1. High Voltage Terminal Strip

2. Compressor Relays

3. Condenser Fan Contactor
4A. Compressor Contactor (Circuit A)
4B. Compressor Contactor (Circuit B)

5. Low Voltage Terminal Strip

6. High Limit Safety Control – Direct Gas-Fired units
only

Refrigeration Components

7A. Compressor (Circuit A)
7B. Compressor (Circuit B)
8A. High Pressure Sensor (Circuit A, Manual Reset)
8B. High Pressure Sensor (Circuit B, Manual Reset)
9A. Thermostatic Expansion Valve (TXV) (Circuit A)
9B. Thermostatic Expansion Valve (TXV) (Circuit B)
10A. Refrigerant Distributor (Circuit A)
10B. Refrigerant Distributor (Circuit B)

11. Condensate Drain (P trap here)

Additional Control Components

In addition to the control components located in the
PDX module, various high- and low-voltage circuits are
found in the Make-Up Air Unit control center. See the
unit-specific wiring diagram (found in the unit control
center) for complete information.

Typical Unit Control Center

1. Power Distribution Block - field-supplied power
from main disconnect switch is terminated here.

2. Phase Monitor has jumpers going to power
distribution block)

3. Transformer provides 24 VAC to various low voltage
devices including the Phase Monitor and to Low
Voltage Terminal Strip in compressor compartment.

4. Relays RC1 and RC2 are wired to the control
center in the compressor compartment.

5. Low Voltage Terminal Strip - Switch S4 terminates
here.

6. Thermostat TS5 monitors outdoor air temperature
and turns the DX unit on or off.

7. Inlet Air Sensor monitors the incoming air
temperature and will disable the DX unit if ambient
temperatures are too low.

Phase Monitor constantly checks for
loss of a phase, phase unbalance or
phase reversal. It requires 24 VAC to
operate. When a fault is detected, it cuts
off the power supply to the low voltage
terminal strip, disabling all motors. It has
two LED indicator lights, showing “on”
and “fault”.

Switch S4 (not shown) is terminated on
Low Voltage Terminal Strip 5 above. S4
is field-supplied and field-installed unless
ordered from the factory. See the unit
specific wiring diagram.

Thermostat TS5 monitors outdoor
air temperature. It is field-adjustable. If
there is more than one cooling circuit, an
additional controller for the second stage
will be provided.

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Packaged DX Module for Make-Up Air Unit

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