Stulz SCS-024, SCS-036, SCS-018, SCS-060, SCS-MC-015 Installation, Operation And Maintenance Manual

Mini-Space EC

DX and CW
4 – 12 kW Systems

Vertical Floor Mounted, 60 Hz Data

Installation, Operation and Maintenance Manual

Mini-Space EC Floor Mounted Systems

Model Nomenclature

CCXXXXXEC

CC Air Pattern Capacity (kW) Refrigerant Circuits Cooling Method Blower Type

Mini-Space Compact

System

Example:
12 kW capacity, downfl ow air pattern, 1 circuit, water-cooled DX, EC fans: CCD121WEC

D=Downfl ow
U=Upfl ow
R=Rear Return
F=Front Discharge

04
06
08
11
12

0
1

A=Air
W=Water
G=Glycol
C=Chilled Water

EC

This document contains information protected by copyright. All rights are reserved. The owner of the equipment for which this manual is
written may photocopy the contents of this manual for internal use only. No part of this document may be photocopied, reproduced, or
translated into another language for use by anyone other than the owner of the equipment for which this manual is written without the prior
written consent of STULZ Air Technology Systems, Inc. (STULZ).

This document contains confi dential and proprietary information of STULZ. Distributing or photocopying this document for external distri­bution is in direct violation of U.S. copyright laws and is strictly prohibited without the express written consent of STULZ.

Unpublished — rights reserved under the copyright laws of the United States and of other countries.
Other brands and tradenames are trademarks of their respective owners.

Copyright 2017 by STULZ Air Technology Systems, Inc.
Printed in the United States of America.
All rights reserved.

STULZ Air Technology Systems, Inc.
1572 Tilco Drive
Frederick, MD 21704
USA

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INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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Table of Contents

1.0 Introduction ..................................................... 1

1.1 General ..............................................................................1

1.2 Product Description .....................................................1

1.3 Safety ................................................................................1

1.3.1 General ..............................................................................1

1.3.2 Safety Summary .............................................................1

1.4 General Design...............................................................3

1.4.1 Electric Box Access ......................................................3

1.4.2 Circuit Breakers / Motor Start Protectors ............3

1.4.3 Heaters (Optional) .........................................................3

1.4.4 Coil ......................................................................................4

1.4.5 EC Fan ...............................................................................4

1.4.6 Temperature/Humidity Sensor .................................4

1.4.7 Controller ..........................................................................4

1.5 Optional Equipment ......................................................4

1.5.1 Humidifi er (Optional) ....................................................4

1.5.2 Condensate Pump ........................................................4

1.5.3 Smoke Detector ............................................................4

1.5.4 Firestat .............................................................................4

2.0 Installation ....................................................... 5

2.1 Receiving the Equipment ............................................5

2.2 Site Preparation .............................................................5

2.3 Rigging ..............................................................................6

2.4 Mounting/Placement ...................................................6

2.4.1 Outdoor Equipment ......................................................7

2.5 Optional Equipment (Field Installed) ....................... 7

2.5.1 Floor Stand ......................................................................7

2.5.2 Plenum Box Assembly .................................................7

2.5.3 Remote Display ..............................................................7

2.5.4 Condensate Pump ........................................................8

2.5.5 Remote Temperature/Humidity Sensor ................8

2.5.6 Remote Water Detector ..............................................8

2.6 Air Distribution Connection ........................................8

2.6.1 Downfl ow Confi guration Air Patterns

(CCD/CCF) .......................................................................8

2.6.2 Upfl ow Confi guration Air Patterns

(CCU/CCR) ......................................................................8

2.7 Piping Connections ......................................................9

2.7.1 Refrigerant .......................................................................9

2.7.1.1 Self-Contained Systems .............................................9

2.7.1.2 Split Systems ..................................................................9

2.7.2 Water/Glycol, Chilled Water and Hot Water

Reheat Piping ..............................................................12

2.7.3 Pump Package ............................................................12

2.7.4 Condensate Drain Line ............................................. 12

2.7.4.1 Gravity Drain .................................................................12

2.7.4.2 Condensate Pump .....................................................12

2.7.5 Humidifi er .....................................................................12

2.8 Utility Connections .....................................................13

2.8.1 Main Power ................................................................... 13

2.8.1.1 Single-Phase Units 208/230V ............................14

2.8.1.2 Three-Phase Units .....................................................14

2.8.2 Controls .........................................................................14

2.8.3 Optional Equipment ...................................................14

2.8.3.1 Condensate Pump .....................................................14

2.8.3.2 Remote Temperature/Humidity Sensor .............14

2.8.3.3 Remote Water Detector ...........................................15

2.8.4 Split Systems ...............................................................15

2.8.4.1 Glycol Systems ............................................................ 15

2.8.4.2 Remote Condenser....................................................15

2.9 System Charging Procedures ................................15

2.9.1 Water-Water/Glycol Cooled Systems ...................15

2.9.2 Pump ..............................................................................15

2.9.3 Remote Air-Cooled Systems .................................. 15

2.9.4 Estimating Refrigerant Charge ..............................17

2.9.4.1 Preparing the System For Charging ..................... 17

2.9.4.2 Evacuate the System .................................................17

2.9.4.3 Refrigerant Charging Procedure .............................18

2.9.4.4 -30 °F Ambient Applications .................................. 19

2.10 System Settings and Adjustments ....................... 19

2.10.1 Low/High Pressure Limit Switch .........................19

2.10.2 Head Pressure Controls-Air Cooled Systems ..20

2.10.2.1 -20°F Condenser Fan Speed ................................20

2.10.2.2 -30°F Flooded Head Pressure Control ..............20

2.10.3 Head Pressure Controls-Water/Glycol

Cooled Systems ..........................................................20

2.10.4 Humidifi er Adjustment .............................................. 20

2.10.5 Thermal Expansion Valve .........................................20

2.10.6 Hot Gas Reheat (Optional).......................................21

2.10.7 Snap Acting Hot Gas Bypass (Optional) .............21

2.11 Refrigerant Characteristics .....................................21

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2.11.1 Pressure/Temperature Settings ...........................21

2.11.2 Saturated Refrigerant Pressure ............................ 21

3.0 Start-Up/Commissioning .............................22

3.1 Operation ......................................................................22

3.2 Step-by-Step Start-Up Instructions ....................22

3.3 Unit Shutdown ............................................................. 22

3.4 Microprocessor Controller Programming .........22

4.0 Maintenance .................................................. 23

4.1 Periodic General Maintenance ..............................23

4.1.1 Filter ................................................................................23

4.1.2 Drain Pan .......................................................................23

4.1.3 Coils ................................................................................23

4.1.4 Heat/Reheat ................................................................23

4.1.5 Humidifi er ...................................................................... 23

4.1.6 Condensate Pump .....................................................24

4.1.7 Condenser .................................................................... 24

4.1.8 Pump Package ............................................................24

4.2 Troubleshooting ..........................................................24

4.3 Field Service .................................................................28

4.3.1 Leak Detection ............................................................ 28

4.3.2 Leak Repair .................................................................. 28

4.3.3 Refrigerant Piping ......................................................28

4.3.4 General Common Repairs/Component Re-

placement ..................................................................... 28

4.3.4.1 Compressor Failure ..................................................28

4.3.4.2 Standard Clean out Procedure .............................. 29

4.3.4.3 Burn-Out/Acid Cleanup Procedure .....................29

4.3.4.4 Humidifi er Cylinder Replacement ......................... 29

4.3.4.5 Filter Replacement ....................................................30

Figures

Figure 1. Typical Upfl ow Internal Layout (Model

CCU041AEC shown for reference) ..............3

Figure 2. Installation Clearance ..............................................5

Figure 3. Typical Installation .....................................................6

Figure 4. Optional Floor Stand Installation .........................7

Figure 5. Downfl ow Confi guration Typical Air

Patterns ..................................................................... 10

Figure 6. Upfl ow Confi guration Typical Air Patterns.....11

Figure 7. Condensate Pump .................................................13

Figure 8. Sample Nameplate ................................................13

Figure 9. Interconnecting Field Wiring - Glycol

Systems ..................................................................... 16

Figure 10. Interconnecting Field Wiring - Remote

Condenser ................................................................ 16

Tables

Table 1. Equivalent Line Size Chart .....................................9

Table 2. Recommended Liquid Line Sizes ........................9

Table 3. Recommended Discharge Line Sizes ............. 12

Table 4. Estimated Refrigerant Charge Weight

for STULZ SCS Condensers ..............................17

Table 5. Weight of R410A Refrigerant

(lbs/100 ft of type L tubing) ...............................17

Table 6. R410A Pressure/Temperature Settings .......21

Table 7. R410A Refrigerant Pressure ............................. 21

Table 8. Troubleshooting Guide .........................................25

5.0 Product Support ............................................30

5.1 Technical Support ......................................................30

5.2 Obtaining Warranty Parts ........................................30

5.3 Obtaining Spare/Replacement Parts..................31

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1.0 INTRODUCTION

1.1 General

The Mini-Space EC™ fl oor mounted precision air conditioning
system covered by this manual is designed and manufactured
by STULZ Air Technology Systems, Inc. (STULZ) using
the latest state-of-the-art control technology. The unit
will provide years of trouble free service if installed and
maintained in accordance with this manual. Damage to the
unit from improper installation, operation or maintenance is
not covered by the system warranty.

Study the instructions in this manual; they must be followed
to avoid diffi culties. Spare parts are available from STULZ
to insure continuous operation. Using substitute parts or
bypassing electrical or refrigeration components in order
to continue operation is not recommended and will void the
warranty. Due to technological advancements, components
are subject to change without notice.

Mini-Space EC systems and centrifugal condensers are
designed to be installed indoors, unless otherwise noted on
the equipment. Propeller-type condensers, drycoolers and
pump packages are designed for outdoor use.

1.2 Product Description

The DX-based versions of the Mini-Space EC precision A/C
system are available in air-cooled, water-cooled and glycol­cooled confi gurations. A chilled water confi guration of the unit
is also available. The cooling capacity in kW will depend on
the unit size, which can range from 4kW (12 MBH) to 14 kW
(48 MBH). Mini-Space EC systems are designed to operate
with R410A refrigerant.

NOTE

Mini-Space EC systems are designed to supply air
to only one room.

The functional modes of operation in addition to cooling are
heating, humidifi cation, dehumidifi cation and fi ltration, which
provide complete environmental control of a conditioned
space. The cabinet is available in one footprint size: A compact

23.8 inches wide by 22.7 inches deep.
The cabinet is designed for convenient, 100% front access.

There are four airflow pattern configurations; upflow,
downflow, rear return, and front discharge. The basic
cabinet height remains the same, (72.8”), regardless of the
confi guration. An optional plenum box may be selected (for
upfl ow and rear-return units only), which adds an extra 18.5”
to the height. See the installation drawing provided with your
unit for the layout and dimensions of the cabinet.

The Mini-Space EC unit is provided with a factory-mounted
main power disconnect switch with a lockable handle. The
disconnect switch electrically isolates the unit during routine
maintenance. The system incorporates state-of-the-art
component protection with the use of motor start protectors
and circuit breakers.

Mini-Space EC units have a STULZ E² series microprocessor
controller that provides a full alarm system, status monitoring,
cooling/humidifi cation control, multi-system networking and
BMS integration.

1.3 Safety

1.3.1 General

Note, caution and warning statements are used in this
manual to draw attention to important operational and safety
information.

• A bold text NOTE marks an important detail.

• A bold text CAUTION safety alert conveys
information important for protecting your equip­ment and performance. Be especially careful to
read and follow all cautions that apply to your
application.

• A bold text WARNING safety alert conveys
information important for protecting you from
harm. Pay very close attention to all warnings
that apply to your application.

A safety alert symbol   precedes a general WARNING
or CAUTION statement.

An electrical shock symbol   precedes an electrical
shock WARNING safety statement.

1.3.2 Safety Summary

The following statements are general guidelines. They are
followed by warnings and cautions applicable to the Mini­Space EC system.

• Prior to performing any installation, operation,
maintenance or troubleshooting procedure
read and understand all instructions, recom­mendations and guidelines contained within
this manual.

• Never operate the unit with any cover, guard,
screen panel, etc., removed unless the instruc­tions specifi cally state otherwise, and then do
so with extreme caution to avoid personal injury.

• Never lift any component in excess of 35
pounds without help. If a lifting device is used
to move a unit, ensure it is capable of support­ing the unit.

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• When working on electrical equipment, remove
all jewelry, watches, rings, etc.

• Always disconnect the main power supply to
the equipment at the main power disconnect
switch before beginning work on the equipment.
A lock-out/tag-out procedure should be fol­lowed to ensure that power is not inadvertently
reconnected.

• Never work on electrical equipment unless an­other person who is familiar with the operation
and hazards of the equipment and competent
to administer fi rst aid is nearby.

• All personnel working on or near equipment
should be familiar with the hazards associated
with electrical maintenance. Safety placards/
stickers have been placed on the unit to call
attention to personal and equipment damage
hazards.

• Certain maintenance or cleaning procedures
may call for the use and handling of chemicals,
solvents, or cleansers. Always refer to the manu­facturer’s Safety Data Sheet (SDS) prior to using
these materials. Clean parts in a well-ventilated
area. Avoid inhalation of solvent fumes and
prolonged exposure of skin to cleaning solvents.
Wash exposed skin thoroughly after contact
with solvents.

WARNING

This equipment should be serviced and repaired
only by a journeyman refrigeration mechanic or air
conditioning technician.

WARNING

This unit employs high voltage equipment with
rotating components. Exercise extreme care to
avoid accidents.

WARNING

Hazardous voltage will still be present inside the
electric box at the motor start protectors and
circuit breakers when the unit is turned off at the
microprocessor controller. To isolate the unit for
maintenance, turn off power at the main power
disconnect switch. Always disconnect main power
prior to performing any service or repairs.

WARNING

Refrigerant (R410A) is used with this equipment.
Death or serious injury may result if personnel fail

to observe proper safety precautions. Great care
must be exercised to prevent contact of liquid
refrigerant or refrigerant gas, discharged under
pressure, with any part of the body. The extremely
low temperature resulting from the rapid expansion
of liquid refrigerant or pressurized gas can cause
sudden and irreversible tissue damage.

As a minimum, all personnel should wear thermal
protective gloves and face-shield/goggles when
working with refrigerant. Application of excessive
heat to any component will cause extreme pressure
and may result in a rupture.

Exposure of R410A refrigerant to an open fl ame or a
very hot surface can cause a chemical reaction that
forms fl uorophosgene (carbonyl fl uoride), a highly
poisonous and corrosive gas.

In its natural state, refrigerant is a colorless, odorless
vapor with no toxic characteristics. It is heavier than
air and will disperse rapidly in a well-ventilated area.
In an unventilated area, it presents a danger as a
suffocant.

WARNING

When performing soldering or de-soldering
operations, make certain the refrigeration system is
fully recovered and purged and dry nitrogen is fl owing
through the system at the rate of not less than 1–2
CFM (0.030.06M³/minute).

CAUTION

When the air conditioner is in the cooling mode, the
return air-intake and discharge (supply) openings
must be free of obstructions. Ensure access panels/
doors are secure and latched into position.

CAUTION

Do not use cleaning solvents near open fl ame or
excessive heat. Wear eye protection when blowing
solvent from parts. The pressure-wash should
not exceed 30 psig. Solvent solutions should be
disposed of in accordance with local and state
regulatory statutes.

CAUTION

The unit must be kept in its normal installed
position when moving. If the unit is not kept level
and vertical, damage to the compressor will result.

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1.4 General Design

The Mini-Space EC unit is housed in a steel frame cabinet rated for indoor use. The exterior of the cabinet has a powder coat
fi nish to protect against corrosion. A hinged door on the front of the cabinet gives access to components. Operator controls
are conveniently located on the cabinet door.

Figure 1 depicts a typical internal layout of a CCU041AEC (upfl ow) unit and identifi es the major components. Location of
the major components vary depending on the purchased Mini-Space EC model and options.

EC FAN

COIL

CONDENSATE

DRAIN PAN

COMPRESSOR

RECEIVER

HEATER
(ELECTRIC)

ELECTRIC BOX
(BEHIND FRONT DOOR)

FIRESTAT

SMOKE DETECTOR

T/H SENSOR

HUMIDIFIER

DOOR LATCH
(3 PLACES)

GRAPHIC TERMINA

MAIN POWER
DISCONNECT
SWITCH

FILTER
(BEHIND

FRONT DOOR)

Figure 1. Typical Upfl ow Internal Layout (Model CCU041AEC shown for reference)

1.4.1 Electric Box Access

Electrical components are protected by the front access
door, which is locked in three places. To open the front door,
turn the door locks with the triangular key wrench provided.
The front door is also safety interlocked with the main power
disconnect switch, preventing the door from opening when
the switch is in the “On” position. The switch must be turned
to the “Off” position to gain access to the electric box.

The main power disconnect switch may be used to turn the
unit off for emergency shutdown or when routine maintenance
is performed. The handle of the switch may be locked in the
“Off” position to prevent unintended operation.

1.4.2 Circuit Breakers / Motor Start
Protectors

Individual overload protection is provided by circuit breaker(s)
and motor start protectors. These switches must be manually
reset once the overload condition is cleared.

1.4.3 Heaters (Optional)

Heaters may be furnished for reheating the supply air, as
required to offset the sensible cooling of the system during
the dehumidifi cation cycle, and for the automatic heating
mode. As a standard, electric resistance heating elements are
factory installed in the supply airstream to heat the supply air.

As an option, hot gas reheat may be purchased. A hot gas

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heating coil is factory installed in the supply air stream to heat
the supply air. A valve is provided to control the fl ow of hot gas
through the coil to maintain the correct reheat temperature.

1.4.4 Coil

The cooling and optional hot gas reheating coils are aluminum
fi nned/copper tube construction. The coils are leak tested
and cleaned before installation by the factory.

1.4.5 EC Fan

The unit is equipped with a high effi ciency Electronically
Commutated (EC) fan. EC fans have a brushless motor
equipped with permanent magnets and permanently
lubricated ball bearings. The fan impellers are backwards
curved and attached to the rotor casing. The fan is balanced
and aerodynamically optimized to minimize vibration.

The fan does not use a drive belt. Fan speed is variable via a
010 VDC signal from the system controller. The fan motor is
equipped with integral electronics such as thermal protection,
inverters or fi lters. The fan will not produce AC inverter whine.

1.4.6 Temperature/Humidity Sensor

As a standard for room air control, a temperature/humidity
(T/H) sensor is factory mounted in the return air stream.
The (T/H) sensor monitors the return air conditions and
provides input signal(s) to the system controller to manage
the operation of the A/C unit consistent with the setpoints
entered in the system controller. As an option, sensor(s) may
be shipped loose for fi eld installation. Refer to the electrical
drawing supplied with your unit for details specifi c to your
system.

1.4.7 Controller

Mini-Space EC units have a STULZ E² Series Microprocessor
Controller that provides these general features:

• Full alarm system

• Input/output status monitoring

• Full integrated control of cooling

• Multi-system control and remote communica­tion with building management systems

of the unit. It has a backlit liquid-crystal alphanumeric display
and a set of function keys to navigate through the controller
menus and adjust operating parameters.

A customer-provided BMS may be used to directly interface to
the E² controller. Operating instructions for the E² controller
are provided in the STULZ E² Series Microprocessor
Controller Operators Manual. Refer to that manual for
detailed instructions on operating the system controller.

1.5 Optional Equipment

1.5.1 Humidifi er (Optional)

Mini-Space EC systems may utilize an optional electrode
steam humidifi er. The humidifi er is factory installed inside
the air conditioner and includes fi ll and drain valves and
associated piping. Operation of the humidifi er’s fi ll and drain
cycles is based on water conductivity and is maintained by the
humidifi er controller. An operating manual for the humidifi er
is provided with the unit under separate cover. Refer to that
manual for detailed information about humidifi er operation.

1.5.2 Condensate Pump

An optional condensate pump may be used to remove
condensate from the air conditioner and fl ush water from the
humidifi er. An internal overfl ow safety switch is wired to the
system controller to automatically shut down the precision
A/C system should an overfl ow occur.

1.5.3 Smoke Detector

Optionally mounted in the return air stream, a smoke detector
is used to sense the presence of smoke and signal the
controller when a smoke alarm condition exists.

1.5.4 Firestat

Optionally mounted in the return air stream, a fi re detector
senses high return air temperature and signals the controller
when a fi re alarm condition exists.

The E² controller is mounted inside the unit electric box. User
interaction is through a graphic terminal mounted on the front

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2.0"

2.0"

36.0"

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2.0 INSTALLATION

2.1 Receiving the Equipment

Your Mini-Space EC unit was inspected and tested for defects
before shipment. To ensure the unit is in excellent condition
when you receive it, visually inspect it upon delivery. Carefully
remove the shipping container and all protective packaging.
Open the access panels/doors and thoroughly inspect the
unit interior for any signs of transit-incurred damage. If there
is shipping damage, it must be noted on the freight carrier’s
delivery forms before signing for the unit. STULZ ships all
systems FOB factory. Any freight claims must be done
through the freight carrier. STULZ can assist in the claim
fi ling process with the freight carrier. Should any damage be
present, notify the STULZ Product Support Group before
attempting any repairs. Refer to section on page 30 for
instructions.

A “data package” has been sent with your unit. It contains
this manual; an E² controller manual and, optionally, other
component manuals; system drawings; applicable SDS’s;
a unit startup checklist; a warranty registration form; and
other applicable instructions based on the confi guration
and options of your unit. The data package has been placed
in your unit in a clear plastic envelope. Its documents should
be retained with the unit for future reference.

is especially true for critical/precision room preparation
(computer rooms/labs) requiring close tolerance control of
temperature and humidity. The conditioned space should be
well insulated and include a vapor barrier. The installer should
ensure that the proper insulation rating is used based on
the design of the space, which was the basis for the system
selected. The following chart is a recommended minimum
R-value (thermal resistance) to ensure optimum equipment
operation.

NOTE

Items that have been shipped loose, such as
controllers, temperature sensors, water detectors,
etc., are shipped inside the air conditioner unless
specified otherwise by the customer. The duct
connection plate or plenum box (if applicable) are
placed on top of the air conditioner inside the unit’s
carton. Remove and store these items in a safe place
unless you are using them immediately.

2.2 Site Preparation

Mini-Space EC systems are designed for easy service access.
A component access door is located on the front of the
equipment. To maintain full service access through the front
hinged access door, no permanent obstructions should be
placed within 36 inches of the front of the unit. (See Figure 2).

NOTE

Working clearance requirements need to be
established prior to mounting the unit. Refer to local
and national electrical codes.

To minimize the effects of the environment surrounding
the conditioned space, certain steps must be taken. This

Figure 2. Installation Clearance

Structure RValue

Ceiling R38

Wall R21

Floor R19

Door R5

The vapor barrier is the single most important requirement for
maintaining environmental control in the conditioned space.
The vapor barrier in the ceiling and walls can be a polyethylene
fi lm. Concrete walls and fl oors should be painted with a rubber
or plastic based paint. Doors and windows should be properly
sealed and a door sweep used to minimize leakage. Outside or

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fresh air should be kept to a minimum (as it adds to the cooling,
heating, dehumidification and humidifying loads), while
maintaining the requirement of the Indoor Air Quality (IAQ)
standard. Lack of these steps can cause erratic operation,
unstable room control and excessive maintenance costs.

2.3 Rigging

Mini-Space EC systems are designed to be kept vertical.
Move the unit with a suitable device such as a forklift, pallet
jack or roller bar and dollies. A weight table is provided on the
installation drawing provided with your unit for reference. The
Mini-Space EC unit is shipped on a skid to facilitate moving
prior to installation. The unit should always be stored indoors
in a dry location prior to installation.

UPFLOW

OPTIONAL 2 OR 3 WAY PLENUM BOX
(FIELD INSTALLED)

CAUTION

When moving the unit, it must be kept level and
vertical to prevent damage.

2.4 Mounting/Placement

Mini-Space EC systems that are not ducted are designed to
be located in the conditioned space. Ducted units may be
located either inside or outside the space to be conditioned,
but are designed to supply air to only one room. Mini-Space
EC units have a compact footprint which allows them to
be placed in a corner. It is recommended that the unit be
positioned to obtain optimum air circulation.

DOWNFLOW

OPTIONAL DUCT

6

OPTIONAL FLOOR STAND

Figure 3. Typical Installation

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

"FRONT" LABEL

THREADED ROD

MIDDLE HEX NUT

TOP HEX NUT

FLOOR STAND LEG

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NOTE

Placement of the floor or ceiling registers is
important. If they are too close to the unit, the supply
air will be recirculated back to the unit before it has
circulated throughout the space.

See Figure 3. The unit is designed to be located on top of the
fl oor (typically upfl ow) or on a raised fl oor (typically downfl ow).

The Mini-Space EC has a frame and panel construction
for unit rigidity and full service accessibility while the unit is
mounted in place. Ensure the mounting surface is capable of
supporting the weight of the equipment. Before mounting the
unit, refer to the installation drawing for the weight of your unit.

If a fl oor stand is employed, (described in section 2.5.1, “Floor
Stand” refer to the installation drawing provided and cut out
the raised fl oor to match the unit’s overall base dimension.
If a fl oor stand is not selected, use the installation drawing
and cut out the raised fl oor to match the blower discharge
opening and cut out the holes required for piping and wiring
through the raised fl oor.

CAUTION

Ensure the mounting surface can support the
weight of the equipment. On some raised floor
installations a fl oor stand is required, depending on
the load capacity of the existing raised fl oor. Before
mounting the unit, refer to the weight table on the
installation drawing. Equipment must be level to
operate properly.

2.5 Optional Equipment (Field Installed)

NOTE

Do not mount any optional equipment on unit access
doors.

2.5.1 Floor Stand

Install the optional fl oor stand directly on the sub-fl oor, ensuring
the side with the “FRONT” label is facing the same direction
as the front of the unit (see Figure 4). Refer to the fl oor stand
assembly drawing for the dimensions required to cut the raised
fl oor. The fl oor stand is designed with adjustable feet on all the
legs, allowing for leveling and overall height adjustment. Refer
to the fl oor stand assembly drawing for minimum and maximum
height adjustability of your fl oor stand. To adjust the height, fi rst
loosen the middle nuts on each leg. Next, turn the top hex nuts
to raise or lower the fl oor stand. Once the fl oor stand is level
and even with the raised fl oor, lock all feet in place by tightening
the middle hex nuts against the top hex nuts.

2.4.1 Outdoor Equipment

Before installing outdoor equipment, refer to the installation
manual provided with the equipment. Install the equipment
(remote condenser, fl uid cooler, pump package) in a secure
location where it cannot be tampered with and the main
power disconnect switch cannot be inadvertently turned
off. Provide a solid base capable of supporting the weight of
the equipment. Mount the equipment to the base to prevent
it from moving during operation. It is recommended that
outdoor equipment be mounted with vibration isolators to
reduce the vibration transmitted to the mounting surface.

Locate remote condenser/condensing units where the
blower(s) are not likely to draw dirt and debris into the coil
fi ns. There should be at least 24 inches of clearance around
the condenser to ensure adequate airfl ow to the coil.

Install a pump package (if applicable) in accordance with the
installation manual and piping diagram provided with the unit.
The pump should be at least 3 feet below the height of the
expansion tank. Do not form piping loops adjacent to the pump.
Avoid piping very rigid lines.

Figure 4. Optional Floor Stand Installation

2.5.2 Plenum Box Assembly

If an optional 2- or 3-way air distribution plenum box is
purchased it is typically shipped loose. To install a plenum
box, fi rst apply a strip of sealing foam around the top fl ange
of the A/C unit or run a bead of silicone sealant. Place the
plenum assembly on top of the unit (see Figure 6). Attach the
plenum with self-tapping screws (customer supplied). Holes
are pre-drilled in the plenum box. Remove the front grille for
access to the mounting holes.

2.5.3 Remote Display

An E² controller is supplied with the Mini-Space EC system.
As an option, a factory supplied control panel may be remote
mounted. For mounting and wiring instructions, refer to the
system drawings and E² controller manual sent in the data
package with your unit.

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2.5.4 Condensate Pump

If an optional fi eld-installed condensate pump is included, it
should be located as near as possible to the air conditioning
system. The pump should be positioned so the inlet hole in
the pump is below the drain pan inside the A/C unit. Secure
the pump in place with a mounting clamp or use an adhesive
that is appropriate for the mounting surface. Ensure the pump
is level for proper operation.

2.5.5 Remote Temperature/Humidity Sensor

The remote temperature/humidity (T/H) sensor must be
located so that it will properly sense the temperature/humidity
conditions to be controlled. The T/H sensor should not be
mounted near a doorway or an area where it would be exposed
to direct sunlight. When locating the sensor, consider the
length of wire to be used. As an option, a 75 foot or 150 foot
long cable may be provided by STULZ. Follow the steps below
to mount the sensor.

1. Remove the cover from the base of the sensor by squeez­ing it at the top and bottom.

Spot-type water detector

Remove the protective cover and connect two control wires
to the terminals on the base (terminal lugs are provided). Place
the water detector(s) on the fl oor with the metal electrodes
facing down.

The base is provided with a
mounting hole in the center
which may be used to secure
the water detector in place.
Replace the cover. When water
is present, current will flow
between the electrodes.

NOTE

Do not place the spot-type water detector on an
electrically conductive surface.

Cable type water detector

Lay the cable water detector fl at across the sub fl oor where
water could collect. When water is present, current will fl ow
between the two wires.

A two conductor wire harness is provided with a quick
connect fitting on the end.
The harness mates to the
fi tting on the water detector
and connects it to the control
board inside the electric box.

CAUTION

The sensor can be damaged if handled improperly.
Take care to not touch the sensor as this may affect
its accuracy.

2. Place the base temporarily against the mounting surface.

3. Level the base. Mark and drill mounting holes through at
least two of the available slotted holes.

4. Run a three-conductor shielded cable through the
opening in the base, then secure the base with screws
ensuring the word TOP on the PC board is oriented
upward.

5. Make the wiring connections. Refer to section 2.8.3.2
on page 14 and the wiring diagram supplied with your
unit.

6. Seal the hole in the wall behind the sensor.

7. Replace the cover plate on the base.

2.5.6 Remote Water Detector

The remote water detector is normally placed on the sub fl oor
or in a fi eld-supplied auxiliary drain pan located beneath the
unit. STULZ provides two types of water detectors, installed
as described below.

2.6 Air Distribution Connection

If ductwork is to be installed always consult your local or state
codes. The duct system should be designed to allow the air
to move with as little resistance as possible.

2.6.1 Downfl ow Confi guration Air Patterns
(CCD/CCF)

In a downfl ow unit the conditioned supply air discharge is
through the bottom of the unit into a raised fl oor or through
the front door into the conditioned space. There are two basic
return air patterns: top free return and top ducted return (see
Figure 5).

2.6.2 Upfl ow Confi guration Air Patterns
(CCU/CCR)

In an upfl ow unit the conditioned supply air has two methods
of discharge from the top of the unit: Ducted or through a 2
or 3-way grilled plenum box. There are two basic return air
patterns: Front free return or rear ducted return (see Figure 6).
Units with a rear ducted return are provided with a duct fl ange
for connection of the ducting (refer to the installation drawing
provided with the unit). The connection of the duct to the unit
may be made with either pop rivets or self-tapping screws.

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2.7 Piping Connections

2.7.1 Refrigerant

2.7.1.1 Self-Contained Systems

No refrigerant connections are required for self-contained,
water/glycol-cooled systems (models CC( )-041/121W/G­EC) and chilled water systems (models CC( )-110CWEC).

2.7.1.2 Split Systems

Split air-cooled systems with a remote condenser will require
fi eld installed refrigerant piping. All split systems are shipped
with a dry nitrogen charge of 50 psig.

NOTE

Mini-Space EC units are not available in a remote
condensing unit confi guration.

Split systems coupled with a remote condenser will require a
copper discharge line and copper liquid line. The connections
are made outside the cabinet. The pipe stubs are labeled; for
example, “Discharge,” “Liquid.” See the installation drawing
for size and location.

All refrigeration piping should be installed with high
temperature soldered joints. Use standard refrigeration
practices for piping supports, leak testing, dehydration and
charging of the refrigeration circuits. The refrigeration piping
should be isolated from the building by the use of vibration­isolating supports. To prevent tube damage when sealing
openings in walls and to reduce vibration transmission, use a
soft fl exible material to pack around the tubes.

Clear all pipe connections of debris and prepare the
connections for soldering. Use only “L” or “K” grade refrigerant
copper piping. Be careful not to allow solder/piping debris to
get inside refrigerant lines. Silver solder containing a minimum
of 15% silver is recommended. Dry nitrogen should be fl owing
through the tubing while soldering at a rate of not less than
12 CFM (.03 - .06 m3/minute).

Refrigerant lines for split systems must be sized according
to the piping distance between the evaporator and the
condenser/condensing unit. Each valve, fi tting and bend in the
refrigerant line must be considered in this calculation. Refer
to the following chart provided for determining the standard
equivalent lengths, in feet, of straight pipe.

When installing remote condenser(s) above the evaporator,
the discharge line should include a shallow P-trap at the
evaporator. The highest point in the discharge line should be
above the condenser coil. An inverted trap is required on the
discharge line at the remote condenser to help prevent oil
and liquid refrigerant from fl ooding back to the compressor.

Oil traps must be included every 20 feet in the vertical risers
and the refrigerant lines must be sloped ¼ inch for every 10

feet in the horizontal lines to ensure proper oil return to the
compressor.

Refer to the line size charts provided in Table 1 for
recommended line sizing.

*”Equivalent Ft.” listed in Table 1 through Table 3 accounts for the linear pipe
length as well as equivalent length of valves, elbows and Tee’s.

Table 1. Equivalent Line Size Chart

Equivalent Length (ft) of Straight Pipe

OD (In.)

Line Size

1/2 9.0 5.0 0.9 0.4 0.6 2.0

5/8 12 6.0 1.0 0.5 0.8 2.5

7/8 15 8.0 1.5 0.7 1.0 3.5

1 1/8 22 12 1.8 0.9 1.5 4.5

1 3/8 28 15 2.4 1.2 1.8 6.0

1 5/8 35 17 2.8 1.4 2.0 7.0

2 1/8 45 22 3.9 1.8 3.0 10

2 5/8 51 26 4.6 2.2 3.5 12

3 1/8 65 34 5.5 2.7 4.5 15

3 5/8 80 40 6.5 3.0 5.0 17

Globe

Valve

Angle

Valve

90º

Elbow

45º

Elbow

Tee

Line

Tee

Branch

NOTE

Vertical runs are based on a total rise of 30 equivalent
feet. For greater lengths, individual calculations must
be made. Sizes assume the use of single risers;
double risers may be necessary.

Table 2. Recommended Liquid Line Sizes

Recommended Liquid Line Sizes

(For R410A Refrigerant)

CC() Model No./

Total

BTU Capacity

041 / 12,000 3/8 3/8 3/8

061 / 18,000 3/8 3/8 1/2

081 / 24,000 3/8 1/2 1/2

121 / 36,000 1/2 1/2 1/2

Receiver to Evaporator (Equivalent Length Ft*)

50’ or less 100’ or less 150’ or less

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NON-DUCTED TOP RETURN WITH FRONT AND BOTTOM DISCHARGE

RETURN
AIR INLET

SUPPLY
AIR OUTLET

TOP FREE RETURN/
BOTTOM DISCHARGE

DUCTED TOP RETURN WITH FRONT AND BOTTOM DISCHARGE

SUPPLY
AIR OUTLET

TOP FREE RETURN/
FRONT DISCHARGE

RETURN
AIR INLET

RETURN
AIR INLET

SUPPLY
AIR OUTLET

TOP DUCTED RETURN/
BOTTOM DISCHARGE

Figure 5. Downfl ow Confi guration Typical Air Patterns

DUCT

SUPPLY
AIR OUTLET

TOP DUCTED RETURN/
FRONT DISCHARGE

RETURN
AIR INLET

DUCT

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TOP DISCHARGE WITH 2 OR 3 WAY PLENUM BOX

RETURN
AIR INLET

SUPPLY
AIR OUTLET

SUPPLY
AIR OUTLET

DUCT

DUCT

RETURN
AIR INLET

TOP DUCTED DISCHARGE

SUPPLY
AIR OUTLET

REAR DUCTED RETURNFRONT FREE RETURN

SUPPLY
AIR OUTLET

DUCT

RETURN
AIR INLET

FRONT FREE RETURN

DUCT

RETURN
AIR INLET

REAR DUCTED RETURN

Figure 6. Upfl ow Confi guration Typical Air Patterns

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Consult the Copeland applications data guide for detailed
information regarding refrigerant line traps and line sizing.

Table 3. Recommended Discharge Line Sizes

Recommended Discharge Line Sizes

(For R410A Refrigerant)

CC() Model

No./Total

BTU Capacity

041 / 12,000 1/2 1/2 5/8

061 / 18,000 5/8 5/8 5/8

081 / 24,000 5/8 7/8 7/8

121 / 36,000 7/8 7/8 7/8

50’ or less 100’ or less 150’ or less

Equivalent Length Ft*

2.7.2 Water/Glycol, Chilled Water and Hot
Water Reheat Piping

The piping connections for water/glycol and chilled
water systems are sweat connections. Pipe sizes may not
necessarily be the same size as the unit connection. Piping
should be sized to match the required system pressure drop
and pump capacity (if applicable) and may require reducing
fi ttings to match the connection size on the air conditioner.

Water/glycol/chilled water-cooled systems with low
entering fl uid temperatures should have insulated piping.
The recommended ethylene glycol solution ratio is 40%
glycol to 60% water. (STULZ recommends Dowtherm SR1
manufactured by Dow Chemical Co.) Use only ethylene glycol
with inhibitors for corrosion protection.

WARNING

Glycol is hazardous. Consult the manufacturer’s SDS
for detailed safety information.

CAUTION

When installing and fi lling the water/glycol/chilled
water loop and optional hot water reheat loop, all air
must be bled from the piping system.

CAUTION

The piping system must be fl ushed prior to operating
the system. Failure to do so will result in equipment
problems.

A strainer should be included in the water/glycol/chilled water
line. Once the system is operational, the fl uid runs through the
strainer where any foreign objects are removed. The strainer
screen should be cleaned periodically.

2.7.3 Pump Package

Install a concentric reducer at the pump suction and discharge
openings and make all piping at least one (1) size larger than
the diameter of the openings. If a suction strainer is necessary,
install one with a net area 2–3 times larger than the suction
piping. The piping leaving the drycooler should enter the
pump suction port. Install a check valve in the discharge line
to prevent back fl ow that may damage the pump on shut
down. Install a ball valve in the suction and discharge lines
for maintenance purposes.

2.7.4 Condensate Drain Line

2.7.4.1 Gravity Drain

A drain line is installed to drain the condensate pan. If an
optional humidifi er is used, the drain line from the humidifi er is
typically connected to the condensate drain line. The drain line
is run out of the right side of the cabinet. See the installation
drawing provided with your unit for the size and location of
the condensate drain line.

NOTE

The humidifi er drains (hot) water into the condensate
drain line during normal operation. As an option,
a separate drain line may be provided for the
humidifi er.

The drain line must not be exposed to freezing temperatures.
The diameter of the drain line should be the full size of the
connection.

NOTE

Pour some water into the condensate drain pan(s)
prior to start-up. This fi lls the trap and prevents air
from being drawn up the drain lines.

2.7.4.2 Condensate Pump

An optional condensate pump shown in Figure 7 on page
13 is available for automatic removal of condensate from
the air conditioner and fl ush water from the humidifi er. The
condensate pump must be fi eld installed.

A P-trap is installed in the condensate pan drain line, so one is
not required for the condensate pump. The condensate pump
discharge line should be 1/2 inch OD (maximum) copper
pipe to prevent excessive backfl ow to the condensate pump.

2.7.5 Humidifi er

Mini-Space EC systems use an electrode steam humidifi er. In
most cases the humidifi er empties into the condensate drain
line during the fl ush/drain cycle. As an option, the drain for
the humidifi er may have a separate connection. Refer to the
installation drawing provided with your unit for the size and
location of the connection.

12

INLET 7/8" OD

OUTLET 1/2" OD

Figure 7. Condensate Pump

A water supply line for the humidifi er must be connected to
the end of the copper tubing provided by the factory. Refer
to the installation drawing provided with your unit for the size
and location of the connection. The humidifi er requires normal
tap water for the water supply. If the supply water is high in
particulate, an external fi lter may be needed.

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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power and control fi eld-wiring. It is important to identify the
options that were purchased with the unit in order to confi rm
which fi eld connections are required.

CAUTION

Do not use demineralized water.

Refer to the humidifi er operator’s manual supplied with the
equipment for complete manufacturer’s information on the
humidifi er and the supply water recommendations.

2.8 Utility Connections

2.8.1 Main Power

The Mini-Space EC is available in single or three phase power
in a wide range of voltages. The unit nameplate (see Figure 8)
lists the operating voltage, frequency and phase of your unit
The nameplate also provides the full load amps (FLA), the
current the unit will draw under full design load, the minimum
circuit ampacity (MCA) for wire sizing, and the maximum fuse
or HACR (Heating, Air Conditioning, Refrigeration) breaker
size (MAX FUSE/CKT BKR) for circuit protection. The unit’s
nameplate is located inside the cabinet within the electric box.

NOTE

If the nameplate states MAX FUSE/CKT BKR, it
is required to use fuses or an HACR-type circuit
breaker to protect the system. Other protection
devices are not allowed based upon the product
listing.

The unit is provided with terminals for all required fi eld-wiring.
Refer to the electrical drawing supplied with the unit for all

Figure 8. Sample Nameplate

WARNING

Verify power is turned off before making connections
to the equipment.

NOTE

All wiring must conform to local and national
electrical codes. Only use copper conductors. Wiring
terminations may become loose during transit of
the equipment; therefore, it is required to verify
that all wiring terminations are secure prior to initial
operation.

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CAUTION

Verify facility power to the unit matches the voltage,
phase and frequency specified on the system
nameplate. Supply voltage measured at the unit
must be within ±10% of the voltage specifi ed on
the system nameplate except for 208/230V single­phase units, which have a different tolerance listed in
the sections to follow.

A main distribution panel must be provided with a manual
fused disconnect switch or HACR-type circuit breaker
per local and national electrical codes for service to the
equipment. Do not mount a customer-supplied manual fused
disconnect switch or HACR-type circuit breaker to the surface
of the A/C unit.

The unit is provided with a main power pilot hole and a
control wiring pilot hole for connection of field-wiring
conduits. Typically, these pilot holes are located on the side
of the Mini-Space EC cabinet. A label stating “MAIN POWER
INPUT” is placed in close proximity.

Terminate the main power wires at the line side of the main
power disconnect switch located within the electric box (see
Figure 9). A separate equipment ground lug is provided in the
electric box for terminating the earth ground wire.

The size of the electric box and location of its components
vary according to the Mini-Space EC model. Electric box
components are labeled with reference designators which are
identifi ed by name on the unit electrical drawing contained in
the data package accompanying the unit.

CAUTION

Prior to unit operation, an adequate unit-to-earth
ground must be connected.

2.8.1.1 Single-Phase Units 208/230V

The supply voltage for units that are designed for 208V
operation must have a tolerance within -5% and +10%. If the
measured supply voltage is 230V, the unit can operate with a
tolerance of ±5% if the following change is made. The control
transformers within the system must have the primary wire
connected to its respective 240V tap instead of the 208V tap.

2.8.1.2 Three-Phase Units

Three-phase units are designed to have the L1, L2 and
L3 supply wires connected to corresponding L1, L2 and
L3 line terminals of the non-fused main power disconnect
switch. The unit will operate correctly if the supply wires are
connected in this manner. A ground lug is provided in each
unit near the non-fused main power disconnect switch. Prior
to unit operation an adequate unit-to-earth ground must be
connected to the unit.

CAUTION

Improper wire connections will result in reverse
rotation of the compressor (if applicable) and may
eventually result in damage to the compressor in DX­based systems. To correct this problem, exchange
any two of the incoming main power wires at the main
power disconnect switch. Do not rewire the unit’s
individual components.

2.8.2 Controls

The E² is the standard controller for Mini-Space EC systems.
If the graphic terminal is mounted on the unit (standard),
no utility connection is required. As an option, the graphic
terminal may be factory supplied for remote mounting. A
cable harness is typically provided for the interconnect wiring.
Refer to the STULZ E2 Series Microprocessor Controller
Operators Manual and the electrical drawing supplied with
your unit for details on connecting the graphic terminal.

2.8.3 Optional Equipment

NOTE

All wiring must be provided in accordance with local
and national electrical codes.

2.8.3.1 Condensate Pump

Systems supplied with a fi eld-installed condensate pump
require power and control wiring to be connected to the
unit. After installing the condensate pump, the installer must
connect two power conductors from the condensate pump
main power terminals to the air conditioning unit. A ground
wire must be connected to the unit ground stud located in
the unit electric box.

Two control conductors must be wired to the control terminal
board located in the unit electric box. The control wires from
the terminal board in the electric box should be run through
the overfl ow switch in the condensate pump housing. The
condensate pump is equipped with pigtail leads for splice­type wire connections with twist-on connectors (wire caps).
Refer to the electrical schematic supplied with your unit for
proper wire terminations.

2.8.3.2 Remote Temperature/Humidity Sensor

Each remote temperature/humidity sensor requires a
three-conductor shielded cable with the shield being
terminated at the unit electric box. Both the electric box and
the sensor include a terminal strip with box-type lugs for wire
connections. Refer to the electrical drawing supplied with your
unit for proper wire terminations.

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2.8.3.3 Remote Water Detector

Each remote water detector will require wiring two conductors
to the control terminal board in the unit electric box. The
wire insulation must be rated at 600V. Refer to the electrical
drawing supplied with your unit for proper wire terminations.

2.8.4 Split Systems

The following system interconnecting fi eld wiring sections
detail the number of conductors required for a typical system.
Additional control conductors may be required depending
on the options purchased with the equipment. Refer to the
supplied electrical schematic to determine the total number
of interconnecting conductors required for your system. It is
important to note that the control transformer(s) supplied with
the equipment have been sized and selected based upon the
expected loads for each system.

CAUTION

Do not connect any additional loads to the system
control transformers. Connecting additional loads
to the factory supplied control transformer(s) may
result in overloading the transformer(s).

NOTE

All wiring must be provided in accordance with local
and national electrical codes.

2.8.4.1 Glycol Systems

Systems equipped with a glycol-cooled system/pump
package require fi eld wiring between the glycol unit and
pump package (see Figure 9). The installer must wire two
control conductors from the terminal board in the Mini-Space
EC electric box to the pump package electric box. Refer to
the electrical drawing supplied with your unit for the number
of fi eld wires needed and appropriate wire terminations for
your system.

2.8.4.2 Remote Condenser

Systems equipped with a remote condenser require fi eld
wiring between the Mini-Space EC unit and the remote
condenser (see Figure 10). Refer to the electrical drawing
supplied with your unit and the wiring diagram supplied with
the condenser (typically located in the condenser electric
box). The installer must provide main power wiring to the main
power distribution block located in the remote condenser
control box. A separate equipment ground lug is provided
in the electric box for termination of the earth ground wire.

The installer must also wire control conductors from the
terminal board in the A/C unit to the control terminal board
in the remote condenser electric box. Refer to the electrical
drawing for the correct number of fi eld wires needed and for
the appropriate wire terminations for your specifi c unit.

2.9 System Charging Procedures

2.9.1 Water-Water/Glycol Cooled Systems

No fi eld refrigerant charging is required for fl uid cooled units.
Observe the following precautions when installing and fi lling
the water-water/glycol loop:

• Clean the piping system before water or water/
glycol is allowed to fl ow through the system.

• Mix glycol with water before it is added to the sys­tem. Use only water/glycol solution with inhibitors
for corrosion protection.

• Bleed all air from the piping system before fi lling
the water-water/glycol loop.

1. Open a vent valve at the highest point of the system.

2. Fill the system until the solution is discharging from the
vent with minimal signs of foaming due to air in the system.

2.9.2 Pump

If a pump is used, ensure the system is fi lled before turning the
pump on; if the pump is not self-priming, there must be pressure
on the suction inlet.

CAUTION

Do not run the pump when dry.

If the pump has no pressure on the discharge side, leave the
discharge valve partially shut to create a back pressure in the
pump so that liquid can build up in the impeller housing (to keep
the impeller housing from getting too hot). Make sure there is
always liquid fl owing through the pump to cool the impeller and
housing. If there is no liquid leaving the pump, shut the pump
off immediately to prevent damage to the pump. Check for
proper rotation of the motor, observing the arrow on the side
of the impeller housing.

2.9.3 Remote Air-Cooled Systems

Remote air-cooled systems are provided with a dry nitrogen
holding charge, which must be removed before piping and
charging the unit. Before charging, check the unit nameplate
to confi rm the type of refrigerant to use.

NOTE

Refrigerant charging must be performed by a qualifi ed
air conditioning technician.

Mini-Space EC systems use R410A refrigerant. Refrigerants
that are multi-component blends like R410A have component
parts with different volatilities that result in a change in
composition and saturation temperature as evaporation
and condensation occur. The composition of liquid R410A
refrigerant however, remains relatively constant.

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MAIN POWER SUPPLY

208-460V/1PH-3PH/60Hz

INTERCONNECTING FIELD WIRING

(TO BE INSTALLED IN ACCORDANCE

WITH NFPA 70, N.E.C.)

L1
L2
L3

MAIN POWER SUPPLY
208-460V/1PH-3PH/60Hz

24VAC

MODELS CC()-041/121-W/G

NOTES:

1. PHANTOM WIRES ( ) NOT APPLICABLE FOR SINGLE PHASE POWER SUPPLIES.

2. WIRE CONNECTION POINTS SHOWN IN THE ILLUSTRATION ARE NOTIONAL. POSITION
OF TERMINATION POINTS IN THE CABINET WILL DIFFER FROM THAT SHOWN.

ELECTRIC

BOX

PUMP PACKAGE

(GLYCOL UNITS ONLY)

L1
L2
L3

DRYCOOLER

INTERCONNECTING FIELD WIRING
(TO BE INSTALLED IN ACCORDANCE
WITH NFPA 70, N.E.C.)

Figure 9. Interconnecting Field Wiring - Glycol Systems

MAIN POWER SUPPLY

208-460V/1PH-3PH/60Hz

INTERCONNECTING FIELD WIRING

(TO BE INSTALLED IN ACCORDANCE

NOTES:

1. PHANTOM WIRES ( ) NOT APPLICABLE FOR SINGLE PHASE POWER SUPPLIES.

2. WIRE CONNECTION POINTS SHOWN IN THE ILLUSTRATION ARE NOTIONAL. POSITION
OF TERMINATION POINTS IN THE CABINET WILL DIFFER FROM THAT SHOWN.

WITH NFPA 70, N.E.C.)

L1
L2
L3

MODELS CC()-041/121-W/G

MAIN POWER SUPPLY
208-460V/1PH-3PH/60Hz

L1
L2
L3

24VAC

AIR COOLED CONDENSER

INTERCONNECTING FIELD WIRING
(TO BE INSTALLED IN ACCORDANCE
WITH NFPA 70, N.E.C.)

Figure 10. Interconnecting Field Wiring - Remote Condenser

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CAUTION

PVE oil is used in systems with R410A refrigerant.
PVE oil quickly absorbs moisture when exposed
to air. Acid forms in systems with high PVE oil
moisture levels (via reaction between moisture and
refrigerant), resulting in system contamination. Keep
the entire system sealed as much as possible and
minimize exposure of PVE oil to outside air.

R410A systems operate at high pressures, which must be
considered when checking the operating temperatures/
pressures while charging or troubleshooting the system.
Tables are provided in Section 2.11.1 on page 21 showing
the temperature/pressure characteristics for R410A.

2.9.4 Estimating Refrigerant Charge

When charging a system with R410A refrigerant it will
be necessary to weigh in the refrigerant and confi rm the
charge is correct by checking the superheat and sub-cooling
temperatures (see Section 2.9.4.3 on page 18).

You can estimate the amount of refrigerant needed by adding
the amount of refrigerant required for the A/C unit (3.8 lbs for
all CC()-()-AEC units) plus the condenser (see Table 4) plus
the interconnecting refrigerant piping between the A/C unit
and the condenser (see Table 5). The values in the tables are
the estimated weights for the refrigerant circuit.

Table 4. Estimated Refrigerant Charge Weight

for STULZ SCS Condensers

SCS Model

Number

SCS018 0.5 lbs 2.6 lbs
SCS024 1.0 lbs 5.2 lbs
SCS036 1.5 lbs 7.8 lbs

SCS060 2.2 lbs 11.7 lbs
SCSMC015 0.8 lbs 4.0 lbs
SCSMC018 1.0 lbs 4.2 lbs

Table 5. Weight of R410A Refrigerant

Line Size

O.D.

1/2” 5.88 lbs 1.27 lbs
5/8” 9.44 lbs 2.03 lbs
7/8” 19.62 lbs 4.22 lbs

Table 4 shows the estimated charge weights for STULZ model
SCS condensers. Depending upon site specifi c conditions,

R410A Charge

(less receiver)

R410A Charge
(with receiver)

(lbs/100 ft of type L tubing)

Liquid Line

Discharge

Line

refrigerant may need to be added or removed when fi ne tuning
the charge to obtain the correct superheat and sub-cooling
temperatures.

Example: Estimate the amount of refrigerant required for
a refrigeration circuit in a system using R410A refrigerant
consisting of a CCD041AEC unit connected with a 1/2” x 30
foot liquid line and 5/8” x 30 foot discharge line to a STULZ
Model SCS018 condenser.

A/C Unit = 3.8 lbs
+1/2” Liquid Line- 30  (5.88 /100) = 1.764 lbs
+ 5/8” Discharge Line- 30  (2.03/100) = 0.609 lbs

+ Condenser = 0.5 lbs
Estimated Refrigerant Charge = 6.673 lbs

(Round off to nearest 0.1 lb = 6.7 lbs)

2.9.4.1 Preparing the System For Charging

1. With all the system piping connections made, perform a
dry nitrogen leak detection test on the system. Using dry
nitrogen only, pressurize the system to 150 psig. Ensure
all service and solenoid valves are energized open and
that no part of the system is isolated from the pressurized
nitrogen.

2. Since there is no refrigerant in the system to detect at
this point, leaks may be detected by observing if there’s
been a change in the standing pressure after 12 hours.
A signifi cant drop in pressure (>10 psig) indicates a leak
in the system that needs to be repaired. After the system
is determined to be free of leaks, you may evacuate the
system.

2.9.4.2 Evacuate the System

CAUTION

A proper vacuum must be drawn on the refrigerant
system to remove moisture before charging. If this
is not done, the refrigerant charge will combine with
moisture in the pipes to form an acid that will eventually
lead to compressor failure. A triple evacuation
procedure with dry nitrogen is recommended,
especially for systems with newly installed refrigerant
piping.

NOTE

Use a vacuum pump capable of evacuating the
entire volume of the A/C system, including newly
installed or existing piping. The pump must be in good
operating condition. Ensure it contains clean, fresh
oil. Manufacturers recommend you change the oil in
the pump regularly to maintain its ability to remove
moisture.

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NOTE

Use high quality hoses, and ensure they are free of
defects and don’t leak. To achieve the low vacuum
that must be attained when evacuating the system,
you should use copper tubing instead of hoses if
possible. The use of short, large diameter hoses
helps reduce evacuation time.

1. After ensuring there are no leaks, relieve pressure and
evacuate the entire system while maintaining all the
solenoids open. Pull an initial vacuum of 1500 microns
or lower using the suction and discharge service ports.

NOTE

When pulling a vacuum, the Schrader valves will
unnecessarily restrict the openings, increasing the
evacuation time. It is recommended to remove the
Schrader valve cores with a Schrader valve removal
tool, and draw the vacuum through the port on the
removal tool.

2. If you cannot evacuate the system below 1500 microns,
close the vacuum pump isolation valve and perform a
rate-of-rise test by observing the standing pressure
over time. If the pressure rises slowly (up to 200 microns
in 15 minutes), the system still contains moisture that
needs to be boiled off. Proceed to step #5. If the pres­sure rises rapidly up to atmospheric pressure (more
than 50 microns per minute), there is a leak that wasn’t
detected during step #2. In this case, troubleshoot the
entire system for leaks and repair them, then begin the
initial evacuation process again starting at step #3.

3. If no leaks are detected after the initial vacuum, release
the vacuum and pressurize the system with 23 lbs of
dry nitrogen. Allow the system to stand for two hours with
the dry nitrogen charge. This gives time for the moisture­absorbing nitrogen molecules to disperse in the system.

4. After two hours, release the pressure, then turn on the
vacuum pump and evacuate the system a second time
down to 1500 microns or less. Close the vacuum pump
isolation valve and pressurize the system again with dry
nitrogen and allow the system to stand for two hours as
in step #5.

5. After two hours release the pressure. Turn on the vacuum
pump and complete the process of evacuating the
system, this time with a goal of achieving a 250 micron
vacuum or less. Close the vacuum pump isolation valve.
When you can hold the vacuum at 500 microns or lower
for at least 2 hours with no signifi cant rise in pressure,
the system is ready to charge.

6. Replace the Schrader valve cores if you removed them
during the evacuation steps. You may now introduce the
refrigerant charge through the schrader valves.

2.9.4.3 Refrigerant Charging Procedure

R410A refrigerant must be weighed in when performing
the charge. Refer to section 2.9.4, “Estimating Refrigerant
Charge” and calculate the estimated amount of refrigerant
needed for your system.

When charging a system using a blended refrigerant, it is
essential that the composition of the refrigerant is maintained.
To ensure correct composition, introduce the refrigerant
(R410A) into the system in liquid form rather than vapor form.
Cylinders which are not provided with dip tubes should be
inverted to allow only liquid refrigerant to charge the system.
Keeping the temperature of the cylinder below 85 °F will
help maintain the correct refrigerant composition while the
cylinder is emptied.

WARNING

If refrigerant gas is released in an enclosed area,
it may accumulate in low areas and near the fl oor,
displacing available oxygen. If a major leak occurs,
there is a risk of asphyxiation. In such case, the area
should be immediately evacuated and ventilated.
Personnel should remain away from the area until it
is determined to be safe.

2.9.4.3.1 Initial System Charge

Follow the step-by-step instructions below to charge systems
using R410A refrigerant. The initial charge will be performed
by introducing liquid refrigerant to the discharge side of the
compressor or an available liquid line port with the A/C unit

turned off.

1. Bleed air from hoses and break the vacuum by sup­plying liquid refrigerant to the discharge port near the
compressor until the pressure is equalized. This holding
charge allows the low pressure switch to “hold,” enabling
the compressor to operate throughout the process of
charging the system.

2.9.4.3.2 Fine Tuning the System Charge

Once the initial charge is completed, add refrigerant to the
unit while it is running.

CAUTION

An adequate heat load must be supplied to ensure
a proper charge.

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2. Disconnect the refrigerant cylinder from the discharge
side of the compressor and connect it to the suction side.

3. Refer to “3.0 Start-Up/Commissioning” on page 22.
Start the A/C system and use the system controller to
lower the room temperature setpoint 35 °F below actual
room temperature, thus ensuring cooling remains on as
the unit is charged.

4. When fi ne tuning the charge on cool days it may be nec­essary to restrict the airfl ow across the condenser coil to
raise the pressure. The fan closest to the header must be
running. When fi ne tuning the charge, ensure the pres­sures are correct for the type of refrigerant used. Refer
to the tables in section 2.11.1, “Pressure/Temperature
Settings” for the operating temperature and pressure
ranges for R410A refrigerant.

5. Block off a portion of the intake air to the condenser until
a constant discharge pressure can be obtained. This will
lower the possibility of overcharging. Allow the discharge
pressure to rise to 445480 psig and hold it constant.

6. Slowly meter liquid refrigerant through the suction side
while watching the pressure gauges and monitoring
superheat and sub-cooling temperatures.

CAUTION

Add liquid refrigerant slowly to prevent the refrigerant
oil from “washing out” of the compressor.

7. Take a superheat temperature reading near the feeler
bulb from the controller with the temperature measur­ing device being well insulated. The ideal superheat
temperature is 1215 °F. Maximum allowable superheat
temperature is 20 °F.

2.9.4.4 -30 °F Ambient Applications

NOTE

For units designed for -30 °F operation, a receiver
is used to store the refrigerant during the time the
condenser is not using the extra refrigerant charge.

1. Follow steps 19 in section 2.9.4.3, “Refrigerant Charg­ing Procedure” . Once superheat and sub-cooling tem­peratures are stabilized, additional refrigerant must be
added to the receiver.

NOTE

It is important not to exceed 80% of the total
condenser and receiver volume to allow room for
expansion.

2. A refrigerant level sight glass is located on the side of
the receiver to assist the service technician in charging
the air conditioning system. The proper charge can be
determined by viewing the level of refrigerant in the re­ceiver while the unit is running at an elevated discharge
pressure.

3. Keep the air intake to the condenser blocked and
maintain the discharge pressure at 445 psig and hold
it constant. The condenser fan nearest the condenser
header should be operating continuously. All other fans,
if additional fans exist, should be off during this time.

4. Add additional refrigerant charge to the receiver as
needed until the refrigerant level rises to the center of the
sight glass, indicating the receiver is 80% fi lled.

When the refrigerant in the receiver reaches the sight
glass, the unit is fully charged.

CAUTION

Do not exceed 20 °F superheat. Exceeding this
temperature may cause the compressor to fail.

8. While monitoring the pressure, take a sub-cooling tem­perature reading on the output side of the condenser. The
sub-cooling temperature should be 10–20 °F.

9. If necessary, (slowly) add liquid refrigerant to the suc­tion side until the correct sub-cooling temperature is
achieved.

CAUTION

Remove the blockage from the air intake of the
condenser.

10. Fill out the applicable sections of the Warranty Regis­tration and Start-Up Checklist.

CAUTION

Remove the blockage to the air intake of the
condenser.

5. Fill out the applicable sections of the Warranty
Registration and Start-Up Checklist.

2.10 System Settings and Adjustments

2.10.1 Low/High Pressure Limit Switch

Air conditioning systems utilizing thermal expansion valves
are equipped with hermetically sealed high-pressure and
low-pressure switches. These switches are preset by the
manufacturer and cannot be adjusted. The high-pressure
switch opens at 630 psig and has a manual reset. The low­pressure switch opens at 65 psig (± 10) and closes at 105
psig (± 10) and has an automatic reset.

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2.10.2 Head Pressure Controls-Air Cooled
Systems

2.10.2.1 -20°F Condenser Fan Speed

Used for outdoor or indoor installations where ambient
condenser air inlet temperatures may fall to -20°F, variable
speed condenser motor control is used to maintain head
pressure. The fan speed control is a continual modulation
of the motor’s speed. The condenser fan speed controller is
factory installed in the remote outdoor condenser electric box.
The fan speed controller requires no adjustment.

Wire the condenser in accordance with the electrical
schematic and appropriate codes. The fan speed controller
will automatically control the head pressure.

Factory setting: Switch contacts are set to close on a pressure
rise to 440 psig and open at 330 psig. Set point range is 200

to 610 psig. The differential is set at 110 psi and is adjustable.

2.10.2.2 -30°F Flooded Head Pressure Control

Used for outdoor or indoor installations where ambient
condenser air inlet temperatures may fall to -30°F, fl ooded
head pressure control is designed to maintain head pressure
during low ambient conditions. A head pressure control valve
and a receiver is used in the refrigeration circuit to back up
liquid refrigerant into the condenser coil. The head pressure
control valve is a 3-way modulating valve controlled by
discharge pressure.

When the A/C unit begins to operate, the discharge pressure
rises to 330 psig and the condenser fan is cycled on, as
described in Section 2.10.2.1. When ambient temperature
drops, the discharge pressure drops also. When the discharge
pressure drops, the head pressure control valve diverts
discharge gas away from the condenser to the receiver. Liquid
fl ow from the condenser is restricted, causing liquid to back
up in the condenser.

Flooding the condenser reduces the area available for heat
transfer. The desired result is to increase the pressure into the
condenser, maintaining a minimum discharge pressure during
low ambient operation thus ensuring proper condensing
temperature. The head pressure control valve requires no
adjustment.

While the fan is running, the fl ooded head pressure control
valve modulates the amount of discharge gas entering the
receiver. As the pressure increases, the valve diverts more
discharge gas to the condenser, allowing more liquid to fl ow
from the condenser to the receiver.

When using this method of head pressure regulation there
must be enough refrigerant in the system to ensure adequate
charge at the lowest expected ambient temperature in which

the system will be operating. A receiver is used to store the
extra refrigerant when the condenser is not using it.

NOTE

Systems utilizing air cooled condensers must not
have a refrigerant line pressure drop over 14 psig
across the condenser and the interconnecting piping
to the condenser sections. See the line sizing tables
in section 2.7.1.2 on page 9.

2.10.3 Head Pressure Controls-Water/Glycol
Cooled Systems

In a water/glycol condenser, condensing temperature is
maintained by the liquid fl owing through a regulating valve
and then into a liquid-cooled condenser. The regulating
valve opens to increase the liquid fl ow as the refrigerant
pressure rises (or closes as the refrigerant pressure falls).
The regulating valve is factory set for the correct condensing
temperature; however, it can be adjusted to increase or
decrease the condensing temperature.

Head pressure regulating valves are available in 2-way
or 3-way configurations. Refer to the piping diagram to
determine which type valve is provided. The location and
size of regulating valves varies with the size and model of
the A/C unit.

2.10.4 Humidifi er Adjustment

The humidifi er has an adjustable capacity potentiometer on
the humidifi er control circuit board. The potentiometer may
need to be fi eld adjusted if the humidifi er is not supplying
enough capacity for the current room conditions.

It is recommended that if the humidifi er capacity potentiometer
requires adjustment, the adjustment be made in small
increments and verifi ed. Refer to the humidifi er manual sent
with your unit for the capacity potentiometer location.

CAUTION

Adjusting the capacity potentiometer too high may
result in condensate forming in the system.

2.10.5 Thermal Expansion Valve

Mini-Space EC units employ a Thermal Expansion Valve (TEV).
The TEV maintains constant superheat of the refrigerant
vapor at the outlet of the evaporator by metering the fl ow of
refrigerant into the evaporator. Superheat is the difference
between the refrigerant vapor temperature and its saturation
temperature at a given suction pressure. By controlling
superheat, the TEV keeps nearly the entire evaporator surface
active while preventing liquid refrigerant from returning to
the compressor. As a standard, superheat is factory set at
12–15 °F and should not need adjustment.

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2.10.6 Hot Gas Reheat (Optional)

The hot gas reheat option incorporates a hot gas reheat
solenoid valve and a hot gas reheat coil. Under normal
operation when no reheat is required, the hot gas reheat
valve is de-energized and hot gas fl ows directly from the
compressor discharge to the condenser. When there is a call
for reheat, the controller energizes the hot gas reheat solenoid
valve. The hot gas reheat solenoid valve diverts hot gas to the
reheat coil, mounted directly downstream of the evaporator
coil, before it travels to the condenser. No adjustment to the
valve is necessary.

2.10.7 Snap Acting Hot Gas Bypass (Optional)

The snap acting hot gas bypass system provides some
modulated capacity control and freeze protection. The hot
gas bypass system includes a discharge bypass valve that
allows some hot gas from the compressor discharge line to
pass into the evaporator coil in order to maintain a preset
suction pressure.

The snap acting hot gas bypass system also provides freeze
protection for the evaporator coil by limiting the minimum
refrigerant pressure, thereby preventing the surface
temperature of the evaporator coil from dropping below 32 °F.

The normal control setting is 120 psig (suction pressure) read
from the suction (low) side of the compressor as it operates
in full hot gas bypass operation. The valve is factory set and
no adjustment should be necessary. If adjustment is required,
block one half of the coil and remove adjustment cap from the
end of the valve. Using a 3/8 inch Allen wrench, turn clockwise
to increase pressure or counterclockwise to lower pressure.

CAUTION

Do not exceed 20 °F superheat. Exceeding this
temperature may cause failure of the compressor.

2.11 Refrigerant Characteristics

2.11.1 Pressure/Temperature Settings

Table 6 is provided to assist with the normal settings of the
system for R410A refrigerant. Where applicable, minimum

and maximum settings are given along with normal operating
pressures.

Table 6. R410A Pressure/Temperature Settings

R410A Refrigerant Pressure/Temperature Settings

Normal Min. Max.

Sub-cooling °F 10 5 20

Superheat °F 15 10 20

Design Condensing Temp. @ 95°F Ambient 125 105 140

Suction Pressure (psig)- 130 105 155

Fan Cycling Control- Fan On (psig)- 440 330 480

Fan Speed Control (psig)- 440 - -

2.11.2 Saturated Refrigerant Pressure

The refrigerant temperature/pressure table (Table 7) is
provided for reference for R410A refrigerant.

Table 7. R410A Refrigerant Pressure

Temp. Pressure
(°F) (psig)

20 78.4
22 81.9
24 85.5
26 89.2
28 93.1

30 97.0
32 101
34 105
36 109
38 114

40 118
42 123
44 128
46 133
48 137

50 143
55 155
60 170
65 185
70 201

Temp. Pressure
(°F) (psig)

75 218
80 236
85 255
90 274
95 295

100 318
105 341
110 365
115 391

120 418
125 446
130 477
135 508
140 541

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3.0 STARTUP/COMMISSIONING

3.1 Operation

For new installations, ensure the unit is ready to operate
before starting it by completing the Start-up Checklist.

NOTE

A Warranty Registration and Start-up Checklist
is provided in the unit data package. It should be
completed during start-up and sent to STULZ.
This checklist should be used as a guideline for
items that need to be confi rmed during start-up.

Start-up must be performed by a journeyman refrigeration
mechanic or air conditioning technician.

3.2 Step-by-Step Start-Up Instructions

1. Replace all removed access panels and equipment prior
to performing the start-up checks.

2. Apply power to the precision A/C system at the main
power disconnect switch. Turn the system on at the
controller.

3. Ensure that all blowers and fans are rotating correctly
and freely without any unusual noise.

NOTE

The compressor may have a time delay on start-up.

ity in the conditioned space. Once room conditions have
been programmed or set, a repeat visit to the conditioned
site may be required to ensure the humidifi er is meeting
the room’s requirements.

7. Test dehumidifi cation operation by creating a demand
for dehumidification. Decrease the dehumidification
setpoint 10% below the actual room conditions. The
compressor circuit will be energized to begin the dehu­midifi cation process. While in this mode, the room tem­perature may decrease and the reheat function may ac­tivate. As conditions in the room change, you may have to
readjust the setpoint as you check the operation. An
adequate heat load within the space is required.

8. To verify electric reheat, use an amp meter on the heater
circuit to determine if the heater is operational. For hot
gas reheat, use a voltmeter and a point-to-point method
to verify the control signal has energized the hot gas
reheat solenoid coil. For hot water reheat, verify that the
control signal has energized the control valve and the
temperature of the steam or water has decreased as it
passes through the unit.

In all cases, one to six hours might be required to see a
desired level or decrease of humidity in the conditioned
space. Once room conditions have been programmed or
set, a repeat visit to the conditioned site may be required
to ensure the dehumidifi cation mode is meeting the
room’s requirements.

Water/glycol-cooled units have a head pressure
regulating valve that has been factory set. A valve
adjustment may be required based on water
temperatures or water/glycol fl ow conditions at
your site. Valve adjustments are made through
the E2 controller. Refer to the STULZ E
Microprocessor Controller Operators Manual
for instructuions.

4. Test cooling operation by adjusting the temperature
setpoint below the actual room temperature. The com­pressor should come on (in DX units) and the discharge
air should feel cooler than the return air.

5. Test heating operation by adjusting the temperature
setpoint above the actual room temperature. The source
of heat should be energized to increase discharge air
temperature.

6. Test humidifi cation operation by creating a demand for
humidifi cation. Use an amp meter to determine current
draw of humidifi er. Visually check for vapor leaving the
steam head or feel if the cylinder is warm to verify if the
humidifi er is operational. In all cases, one to six hours
might be required to see a desired level or rise of humid-

2

Series

3.3 Unit Shutdown

To shut down the unit, command the shutdown from the BMS
managing the unit or use the graphic terminal connected to
the unit controller to power down the unit, as described in the

STULZ E2 Series Microprocessor Controller Operators
Manual.

To perform an emergency shutdown, set the main power
disconnect switch to the Off position.

3.4 Microprocessor Controller
Programming

The microprocessor controller is factory programmed based
on the optional features selected. Most applications require
no fi eld start-up or program adjustment beyond setting the
current date and time. Separate operating instructions for
the controller have been sent with your unit, including each
feature’s factory “default” setting and the available adjustment
range, if applicable.

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4.0 MAINTENANCE

4.1 Periodic General Maintenance

Systematic, periodic general maintenance of the Mini-Space
EC unit is recommended for optimal system performance.
General maintenance should include, but is not limited to, the
following: replacing fi lters and humidifi er cylinders, tightening
electrical connections, checking the condensate line to
ensure it is free of debris, cleaning the interior of the unit,
inspecting the unit’s components visually, checking the level
of refrigerant and ensuring no moisture is in the refrigerant.

Use copies of the Periodic General Maintenance Checklist
at the back of this manual to record periodic general
maintenance inspections. For assistance, contact the STULZ
Product Support Group. Ensure adherence to all safety
statements while performing any type of maintenance.

WARNING

This equipment should be serviced and repaired by
a journeyman or a qualifi ed refrigeration technician
only.

WARNING

This unit employs high voltage equipment with
rotating components. Exercise extreme care to avoid
accidents and ensure proper operation.

Hazardous voltage will still be present inside the electric box
at the motor start protectors and circuit breakers, even with
the unit turned off at the microprocessor controller. To isolate
the unit for maintenance, turn off power at the main power
disconnect switch. Always disconnect main power prior to
performing any service or repairs.

WARNING

Always recover all refrigerant prior to any system
repairs. Failure to do so may result in system over
pressurization and rupture.

4.1.1 Filter

The filter is usually the most neglected item in an air
conditioning system. To maintain effi cient operation, the fi lter
should be checked at least monthly and replaced as required.
Refer to Section 4.3.4.5 for fi lter replacement instructions.

NOTE

Air cleanliness varies from one space to the next.
Establish a frequency for checking fi lters based on
the conditioned space.

4.1.2 Drain Pan

To ensure proper drainage, inspect the drain pan regularly.
Make sure the drain pan outlet is always free of debris and
ensure the drain pan does not leak.

4.1.3 Coils

Coil(s) should be inspected semiannually and cleaned as
required following standard coil cleaning practices. Using
a brush, clean the coil fins of all debris that will inhibit
airfl ow. This can also be done with compressed air or with a
commercial coil cleaner. Check for bent or damaged coil fi ns
and repair as necessary. Check all piping for signs of leaks.

4.1.4 Heat/Reheat

The heat/reheat equipment should be inspected semi­annually to ensure it is operational. If you have electric heat/
reheat, inspect the heating elements to ensure they are free
of debris.

WARNING

Turn off power to the unit unless you are performing
tests that require power. With power and controls
energized, the unit could begin operating
automatically at any time. To prevent personal injury,
stay clear of rotating components, as automatic
controls may start them unexpectedly.

WARNING

Fluorophosgene, a deadly poisonous gas, is
generated when R410A refrigerant is exposed
to flame. Always ensure adequate ventilation
during refrigeration repairs.

4.1.5 Humidifi er

The steam cylinder has a limited lifetime and must be replaced
periodically. Because water conditions and humidifi er usage
rates vary greatly, it is difficult to establish intervals for
changing the cylinder. Individual maintenance schedules
must be determined for each location, based upon periodic
examination of the humidifi er. A change cylinder light on the
humidifi er cabinet will fl ash yellow in a repeating four-fl ash
pattern when the cylinder requires replacement.

See section 4.3.4.4 for detailed instructions on changing
the cylinder.

CAUTION

Failure to replace the cylinder at the end of cylinder
life may result in humidifi er damage.

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4.1.6 Condensate Pump

The condensate pump should be inspected semi-annually and
cleaned. Ensure that the fl oat works freely. Wipe the fl oat with a
wet cloth and detergent to remove dirt. Clean the tank bottom.
Check the discharge line to ensure it is open and water can
pass through it freely.

4.1.7 Condenser

Maintenance access to the condenser is through one or two
removable panels (depending on the unit model). For air­cooled condensers, clean the condenser coil of all debris that
could inhibit airfl ow. This can be done with compressed air or
with a commercial coil cleaner. Check for bent or damaged
coil fi ns and repair as necessary. On outdoor units in winter, do
not permit snow to accumulate on or around the condensing
unit. Check all refrigerant lines and capillaries for vibration
isolation and support as necessary. Check all refrigerant and
coolant lines for signs of leaks.

CAUTION

The compressor crankcase heater is energized as
long as power is applied to the unit. If the main switch
is disconnected for a long period, do not attempt
to start the condensing unit until eight hours after
applying power. This allows enough time for all liquid
refrigerant to be driven out of the compressor. This
is especially important at low ambient conditions.

4.2 Troubleshooting

Turn off all power to the unit before conducting any
troubleshooting procedures, unless the procedure specifi cally
requires the system to operate. For troubleshooting purposes
the system may be operated with the door open by using a
pair of channel lock pliers to turn the shaft of the main power
disconnect switch to the “On” position. When the switch is
turned on, high voltage will be present inside the cabinet.
Exercise caution to prevent injury. Keep hands, clothing
and tools clear of the electrical terminals and rotating
components. Ensure that your footing is stable at all times.

4.1.8 Pump Package

Routinely examine the areas around the pump motor(s) and
inlets and outlets. Check coolant and piping for signs of leaks.
Examine all wiring for signs of chafi ng, loose connections or
other obvious damage. Examine brackets, motor mounts and
hardware for loose or missing parts or other damage. Lubricate
motor bearings if applicable. (See the instruction manual
provided with the pump package.)

24

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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Table 8. Troubleshooting Guide

SYMPTOM PROBABLE CAUSE RECOMMENDATION

Suction Pressure Too Low a. Loss of refrigerant (excessive bubbles in

sight glass).

Locate leak and repair. Recharge system.

b. Expansion valve stuck or obstructed

(short cycle or continuous running).

c. Clogged drier/strainer (feels cold). Replace with new drier/strainer.

d. Dirty air fi lters. Clean/replace fi lters.

Water/Glycol Valve Fails to Open
or Close

Evaporator Coil Ices a. Low airfl ow. 1. Check fi lters. Replace as needed.

Blower Fails to Start a. Power failure. Check main voltage power source input

Control is Erratic Wiring improperly connected or broken. Check wiring against electrical drawing.

a. Temperature set point too high. Adjust to correct temperature setting.

b. No control power to the valve. Thermostat wired incorrectly. Check wiring

c. Actuator failed. Replace actuator.

b. Temperature setting too low. Increase temperature setpoint (68 °F min.).

c. Discharge air short cycling back to return. Check discharge grille orientation.

d. Low refrigerant charge. Find leak, repair and

b. Control transformer circuit breaker

tripped.

c. Defective contactor. Repair or replace.

d. Condensate Switch Open. Insure unit is level.

e. Motor starter protector tripped Reset motor starter protector and check

Remove and clean or replace valve.

diagram and rewire if required.

2. Check for and clear any obstructions
across or in the (supply) discharge air­stream.

3. Check correct rotation of evaporator
blower.

recharge system.

cable.

Check for short circuit or ground fault; if
none, reset circuit breaker.

Check that condensate pan is draining
properly. Clear obstructions.

amperage of motor. Compare to setting of
motor protector and adjust FLA.

25

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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SYMPTOM PROBABLE CAUSE RECOMMENDATION

Condenser Pressure Too High a. Non-condensable gas or air in system. Recover system and recharge. Replace

drier/strainer. Evacuate to 50 microns and
recharge.

b. Condenser air intake is blocked. Remove debris and clean condenser.

c. Overcharge of refrigerant. Reclaim excess refrigerant from system.

d. Low water fl ow to water-cooled con-

denser.

e. Condenser fan not operating. Check pressure/temperature operating

f. Water/glycol temperature too high. Check fl ow and operation of drycooler.

g. Condenser pressure regulating valve set-

ting too high.

h. Flow of water/glycol too low. 1. Check glycol solution level and concentra-

i. Water/glycol solution not mixed prior to

adding to system.

Condenser Pressure Too Low a. Loss of refrigerant (indicated by bubbles

in sight glass).

b. Condenser fan controls not set

Adjust or repair controls properly.

c. Water regulating valve adjusted

too low.

Noisy Compressor a. Expansion valve stuck in open position

(abnormally cold suction line).

b. Worn or scarred compressor bear-

ings.

c. Liquid slugging. System overcharged. Reclaim excess

d. Scroll compressor not properly phased. Phase correctly at main power source. Do

Reset-determine cause and fi x.

switches and motor. Replace as needed.

Adjust to obtain correct pressure.

tion.

2. Valves not open or partially open. Repair/
replace as needed.

3. Air in system - bleed system.

4. Check all strainers and clean if needed.

Remove solution and premix. Refi ll system.

Locate and repair leak. Recharge system.

Adjust or repair controls.

R410A - Readjust to 440 psig.

Ensure feeder bulb is tight on suction
line. Check operation and superheat.

Replace compressor.

refrigerant.

not rewire compressor.

Compressor Fails to Start a. Temperature setpoint too high. Adjust to desired temperature.

b. Compressor internal overload protector

c. Complete loss of refrigerant charge (low

d. Condenser pressure too high (high pres-

e. Minimum off time has not expired.

26

is open.

pressure safety switch).

sure safety switch).

Check compressor for short circuit or
ground.

Locate and repair leak. Recharge system.

Check condenser for obstructions.

Wait for time to expire.

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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SYMPTOM PROBABLE CAUSE RECOMMENDATION

System Short of Capacity

Compressor Short Cycles

Heater Inoperative a. Fuses blown. Check for short circuit, replace fuse.

Humidifi er Inoperative

Note: See humidifi er
manual for additional help.

a. Low refrigerant (indicated by bubbles in

sight glass).

b. Expansion valve stuck or obstructed

(short cycling or continuous running).

c. Clogged drier/strainer (feels cold). Replace with new drier/ strainer.

d. Reduced airfl ow. Check belt tension, fi lters and clear evapo-

a. Low line voltage causing compressor to

overheat.

b. Dirty or iced over evaporator coil. Defrost and/or clean coil.

c. Reduced airfl ow (when applicable). Check fi lter and belt tension.

d. Lack of refrigerant. Check for leak. Repair and recharge sys-

e. Short cycling of conditioned air. 1. Supply and/or return grilles are incorrectly

f. Remote temperature sensor is improperly

located.

b. Temperature set too low. Increase temperature set point.

c. Overheat switch open. Insuffi cient airfl ow across heater elements.

d. Manual-reset overheat safety switch

tripped.

e. Heater element burned out. Check continuity with an ohmmeter. Re-

a. Water supply has been turned off or not

connected.

b. Humidifi er switch is in “Off” position. Turn switch to “Auto/On” position.

c. Electrical connections are loose. Tighten electrical connections.

d. Humidifi er circuit breaker tripped. Check for over current by the humidifi er

e. Relative humidity is above set point. Adjust humidistat set point.

f. Humidistat yellow status LED is fl ashing. Consult humidifi er manual.

g. Water conductivity is too low. Add a teaspoon of table salt to the water

Check for leaks Repair and recharge
system.

Remove valve and clear obstruction or
replace valve.

rator coil of debris.

Check power source for cause of low line
voltage.

tem.

oriented. Re-orient.

2. Supply and return grilles are too close
together. Move further apart.

3. Insuffi cient heat load. Add temporary heat
load to compensate.

Check for supply registers that may be too
close to thermostat. Relocate if necessary.

Check for dirty fi lters or obstructions that
may reduce airfl ow. Correct or replace as
needed.

Reset manual overheat safety switch (See
item immediately above).

place heater element.

Connect and/or turn on water supply.

electrodes. Drain water from tank and refi ll.
Reset circuit breaker.

through the top of the cylinder. Typically
only required on initial start-up.

27

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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4.3 Field Service

NOTE

Do not attempt to make repairs without the proper
tools.

It may be necessary to perform repairs on the refrigeration
system. If fi eld repairs are necessary, the following procedures
apply.

4.3.1 Leak Detection

Several methods can be used to detect a leak in the
refrigeration system. The most modern and easiest method is
to use an electronic leak detector. Follow the manufacturer’s
directions and any leak can be quickly located. A second
method is to use soap bubbles. Apply a solution of soapy
water with a brush or sponge to the joints and connections
in the refrigeration lines. A leak in the lines will cause bubbles
to form.

NOTE

Use a halogen leak detector capable of detecting
R410A refrigerant.

4.3.2 Leak Repair

When a leak is located, properly reclaim the remaining
refrigerant charge before beginning repairs. Adjacent piping
must be thoroughly cleaned by removing all paint, dirt and oily
fi lm. Use a wire brush, sandcloth or sandpaper and wipe the
area with clean, dry cloths. Protect nearby parts from heat
damage by wrapping with water-soaked cloths.

4.3.3 Refrigerant Piping

When replacing components within the cabinet of the unit,
the following solders are recommended: Silfos alloy for
copper-to-copper (piping discharge or suction line repairs);
silver solder (Stay-Silv #45) and fl ux for copper-to-brass or
copper-to-steel repairs; and a 95% tin to 5% antimony solder
with fl ux for liquid line repairs at the drier, strainer, sight glass,
or expansion valve.

When component replacement is complete, remove all traces
of fl ux. After any repair, pressure check the system and ensure
there are no leaks prior to recharging the system.

4.3.4 General Common Repairs/Component
Replacement

4.3.4.1 Compressor Failure

The compressor is the most important component of a DX
unit. Numerous safety devices are provided to protect the
compressor from failing.

When a compressor fails, determine whether the cause is
electrical or mechanical. An electrical failure is indicated by a
distinct pungent odor once the system has been opened. If a

burnout occurred, the oil will be black and acidic. A mechanical
failure will have no burned odor and the motor will attempt to
run. An abnormal or excessive noise may be present.

Analyzing the oil is the only way to determine the proper
procedure for cleaning the refrigerant system. Acid test kits
are available from several manufacturers for measuring the
acid level in the oil. These are capable of making accurate
acidity measurements, but if they are not available a check
of the oil by sight and smell can give a quick indication if
contamination remains in the system. Since refrigeration
oils vary in color, a sample of the new oil in the replacement
compressor should be removed prior to installation and sealed
in a small glass bottle for comparison purposes. If the oil has
been exposed to refrigerant, the bottle should not be tightly
capped, since the residual refrigerant may create a high
pressure if tightly sealed and exposed to high temperature.

CAUTION

Avoid touching or contacting the gas and oil with
exposed skin. Severe burns will result. Use long
rubber gloves when handling contaminated parts.

All electrical connections should be checked to ensure
they are tight and properly made. Check all circuit breakers,
contactors and wiring. Contactors should be examined and
replaced if the contacts are worn or pitted.

If there is acid in the oil, there has been an electrical failure
which has caused the compressor motor to burn out. The acid
diffuses throughout the refrigeration system and must be
removed by using a burnout fi lter kit before a new compressor
is placed in service. Not only must the compressor be
replaced, but the entire refrigeration circuit must be cleaned
of the harmful contaminants left by the burnout. See section

4.3.4.3, “Burn-Out/Acid Cleanup Procedure” for the proper
procedure.

If there is no acid in the oil, there has been a mechanical failure.
See section 4.3.4.2, “Standard Clean out Procedure” for the
proper cleaning procedure.

CAUTION

Damage to a replacement compressor caused by
improper system cleaning constitutes abuse under
the terms of the warranty and will void the warranty.

CAUTION

POE oil is used in systems with R410A refrigerant. If
a replacement compressor is provided, ensure that
it is fi lled with POE oil before installing.

28

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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4.3.4.2 Standard Clean out Procedure

NOTE

Cleaning operations must be performed by a
journeyman refrigeration mechanic or air conditioning
technician.

1. Turn off power to unit at the main power disconnect

switch.

2. Remove the old compressor and install the new com-

pressor.

3. Remove the liquid line drier and install an oversized

liquid line fi lter-drier (one size larger than the normal
selection size).

4. Evacuate the system according to standard procedures.

Normally, this will include the use of a high-vacuum
pump and a low-vacuum micron gauge for measuring
the vacuum obtained.

5. Recharge the system.

6. Turn on the power at the main power disconnect switch

and start the system at the controller.

4.3.4.3 Burn-Out/Acid Cleanup Procedure

The unit should be cleaned using the suction line fi lter-drier
method.

CAUTION

Avoid touching or contacting the gas and oil with
exposed skin. Severe burns will result. Use long
rubber gloves in handling contaminated parts.

7. Recharge the system through the access valve on the
suction line fi lter-drier.

8. Turn on power at the main power disconnect switch and
start the system at the controller.

9. The permanently installed suction line fi lter-drier permits
small system cleanup to be completed in one service
call. The pressure drop across the suction line fi lter-drier
should be measured during the fi rst hour of operation. If
the pressure drop becomes excessive, the suction line
fi lter-drier should be replaced (See Sporlan Bulletin 40­10, for the maximum recommended pressure drop (PSI)
for the suction line fi lter drier).

10. In 24 hours, take an oil sample. Observe the color and
test for acidity. If the oil is dirty or acidic, replace the suc­tion line fi lter-drier.

11. In 2 weeks, examine oil to determine if another suction
line fi lter-drier change is necessary.

4.3.4.4 Humidifi er Cylinder Replacement

The cylinder is disposable and cylinder life is dependent
on water supply conditions and humidifi er usage. After an
extended period of operation a yellow LED on the humidifi er
cabinet will fl ash in a four-fl ash sequence to indicate the
cylinder is completely used and a replacement cylinder must
be installed. The following procedures should be followed
when replacing the cylinder.

CAUTION

Failure to replace cylinder at the end of cylinder life
may result in humidifi er damage.

NOTE

Cleaning operations must be performed by a
journeyman refrigeration mechanic or air conditioning
technician.

1. Turn off power to the unit at the main power disconnect
switch.

2. Remove the burned out compressor and install the new
compressor.

3. Install a suction line fi lter-drier designed for acid removal.

4. Remove the liquid line drier and install an oversized liquid
line fi lter-drier (one size larger than the normal size for
the unit).

5. Check the expansion valve, sight glass and other controls
to see if cleaning or replacement is required.

6. Evacuate the system according to standard procedures.
Normally, this will include the use of a high-vacuum
pump and a low-vacuum micron gauge for measuring
the vacuum obtained.

NOTE

Decrease the low humidity setpoint below ambient
humidity to allow the cylinder to cool down before
removing the cylinder.

1. Turn the unit off, preferably in a manner that uses the
controller, such as via the graphic controller, BMS or
external shutdown control.

2. Drain the cylinder by switching the “On/Off/Drain” switch
to the “Drain” position. Let the humidifi er drain until no
more water is fl owing out to drain (usually not more than
10 minutes).

3. Turn the humidifi er On/Off/Drain switch to off.

4. Turn off water supply to the humidifi er.

5. Exit the cabinet and disconnect power to the humidifi er
at the main power disconnect switch.

29

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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6. Follow the steps of the cylinder removal, drain valve
cleaning and cylinder installation procedures in the
Nortec MES2 Installation and Operation Manual
provided under separate cover with your unit.

7. Close the Mini-Space EC cabinet door and reconnect
main power at the main power disconnect switch.

8. Turn on the water supply to the humidifi er.

9. Readjust the humidity setpoint.

CAUTION

If the humidifi er is to be shut down for an extended
period, follow the steps of the Extended Shutdown
procedure in the Nortec MES2 Installation and
Operation Manual.

4.3.4.5 Filter Replacement

The filters are behind the front door or in the rear filter
box depending on the configuration of the unit. Ensuring
directional airflow arrows on the filters are correct, insert
the new filters then close and/or replace the access panel.

5.0 PRODUCT SUPPORT

STULZ Product Support provides aftermarket technical
and fi eld support, warranty authorization and part sales to
contractors and end users. Factory authorized services are
available by request and include:

• Factory Authorized Start-up/Warranty Inspec­tion

• Commissioning Assistance

• Break Fix Repair

• Preventive Maintenance Contracts

• Performance Evaluations

• Technician and Owner Training

5.1 Technical Support

The STULZ Technical Support Department is dedicated
to the prompt reply and resolution of issues experienced
with supplied equipment. Please contact (888) 5291266
Monday through Friday from 8:00 a.m. to 5:00 p.m. EST.
After hours support is also available. Please provide your
name and contact information and a support technician will
return your call.

When calling to obtain support, it is important to have the
following information readily available, (information is found
on the unit’s nameplate):

• Unit Model Number (CCXXXXXEC )

• STULZ Sales Order Number

• STULZ Item Number

• Unit Serial Number

• Description of Problem

30

5.2 Obtaining Warranty Parts

All Warranty Parts Authorizations are validated and processed
through the Technical Support Department at (888) 529­1266 Monday through Friday from 8:00 a.m. to 5:00 p.m. EST.
A support technician at STULZ will provide troubleshooting
assistance over the telephone. If it can be determined
that a part may be defective, a warranty authorization for
a replacement part will be processed by STULZ Technical
Support. The replacement part will then be shipped via UPS
ground. If the customer requests that warranty part(s) be
sent by any other method than UPS ground, the customer
is responsible for the shipping charges. If you do not have
established credit with STULZ you must provide a freight
carrier account number.

A written (or faxed) purchase order is required on warranty
parts and must be received prior to 12:00 p.m. for same day
shipment. The purchase order must contain the following
items:

• Purchase Order Number

• Date of Order

• STULZ Stated Part Price

• Customer Billing Address

• Shipping Address

• Customer’s Telephone and Fax Numbers

• Contact Name

• Unit Model Number and Serial Number

The customer is responsible for the shipping cost incurred
for returning the defective part(s) back to STULZ. Return of
defective part(s) must be within 30 days, at which time an
evaluation of the part(s) is conducted and if the part is found
to have a manufacturing defect a credit will be issued.

When returning defective part(s), complete the Return
Material Authorization Tag and the address label provided
with the replacement part. For prompt processing, please
affi x the RMA in a prominent place on the external packaging
of the returned part.

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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5.3 Obtaining Spare/Replacement Parts

Maintaining a recommended spare parts inventory is an
industry best practice for critical facilities. On-site spares kits
reduce downtime and can eliminate the cost of expedited
freight charges. Recommended spares and replacement
parts sales are available through Product Support by fax (301)
6201396, telephone (888) 5291266, or email (parts@
stulz-ats.com).

STULZ accepts Visa and MasterCard. STULZ may extend
credit to its customers; a credit application must be prepared
and approved (this process could take one week).

A 25% minimum restocking charge will be applied on
returned stocked parts that were sold as spare/replacement
parts. If the returned part is not a stocked item, a 50%
restocking charge may be applied. Additionally a Return
Material Authorization Number is required when returning
parts. Repair/replacement parts may be returned for credit
up to 30 days after purchase.

31

STULZ Air Technology Systems, Inc.

Frederick, Maryland USA 21704

Telephone: [phone]

Facsimile: [phone]

Periodic General Maintenance Checks and Services Checklist

Date: ____________________________ Prepared By: ___________________________
Model Number: ____________________________ Serial Number: __________________________
Item Number: ____________________________

Monthly

Filters Blower Section Condensate Drain

  Cleanliness   Blower Turns   Drain is Open
  No Obstructions  Belts (if applicable)  Condensate Pan Safety

Switches Operate Freely
Miscellaneous

  Check Glycol or Chilled Water for Air (bleed as required)
  External Heat Exchanger Clean and Clear of Obstructions
  Humidifi er Cylinder and Controls Operate Properly

Semi-Annually

  Check Refrigerant Charge (bubbles in sight-glass)  Tighten Electrical Connections
  Check Suction & Discharge Pressure   Check Contacts on Contactors

for Pitting

  Check Glycol Solution Concentration in System   Clean Unit as Necessary
  Clean Coils  Test the Glycol Solution

Inhibitors (fl ush if necessary)

  Heat/Reheat Operational  Clean Condensate Pump

Annually

Refrigerant Systems Chilled Water Systems

  Inspect Glycol System for Leaks and Corrosion   Inspect Chilled Water System

for Leaks and Corrosion

  Conduct a Complete Check of All Services Listed  Conduct a Complete Check of

Above and Clean Unit's Interior All Services Listed Above and
Clean Unit's Interior

Notes: ___________________________________________________________________________________

__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________

*** If factory assistance is required for any reason, provide the model number, serial number, and STULZ item

number found on the unit nameplate. This will speed the process and ensure accuracy of information. ***

32

Signature:________________________________

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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Glossary

STULZ STULZ Air Technology Systems, Inc.

BMS Building Management System

BTU/Hr British Thermal Units Per Hour

CFM Cubic Feet Per Minute

CNDCT Conductor

ESD Electrostatic Discharge

º F Degrees Fahrenheit

FLA Full Load Amps

FOB Free on Board

HACR Heating, Air Conditioning, Refrigeration

HP Horse Power

Hz Hertz

IAQ Indoor Air Quality

in. w.g. Inches of Water Gauge

kVA Kilo Volt Amps

kW Kilowatt

LEWT Low Entering Water Temperature

LRA Locked Rotor Amps

MAX CKT
BKR Maximum Circuit Breaker

MAX FUSE Maximum Fuse

MCA Minimum Circuit Ampacity

NEC National Electric Code

NFPA National Fire Protection Agency

PH Phase

pLAN Pico Local Area Network

PSI Pounds Per Square Inch

psig Pounds Per Square Inch Gauge

RLA Run Load Amps

RValue Thermal Resistance

R410A Blended Refrigerant

SDS Safety Data Sheet

SPDT Single Pole, Double Throw

TXV Thermostatic Expansion Valve

V Volt

VAC Volt, Alternating Current

VDC Volt, Direct Current

33

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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Notes

34

INI-SPACE EC INSTALLATION, OPERATION AND MAINTENANCE MANUAL

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Notes

35

STULZ North American Headquarters

STULZ AIR TECHNOLOGY SYSTEMS (STULZ USA) , INC.

1572 Tilco Drive |
Tel: [phone] | Fax: [phone] | [e-mail]

STULZ Company Headquarters

STULZ GmbH

Holsteiner Chaussee 283
22457 Hamburg
[e-mail]

STULZ Subsidiaries

STULZ Australia Pty. Ltd.

34 Bearing Road
Seven Hills NSW 21 47

STULZ Austria GmbH
Industriezentrum NÖ – SÜD,
Straße 15, Objekt 77, Stg. 4, Top 7
2355 Wiener Neudorf

STULZ Belgium BVBA

Ter vure nla an 3 4
1040 Bruss els

STULZ Brasil
Ar Condicionado Ltda.

Rua Cancioneiro de Évora, 140
Bairro - Santo Amaro São
Paulo-SP, CEP 04708010

Frederick, MD 21704

STULZ España S.A.
Avenida de los Castillos 1034
28918 Leganés (Madrid)

STULZ France S. A. R. L.
107, Chemin de Ronde
78290 Croissy-sur-Seine
[e-mail]
STULZ S.p.A.
Via Torricelli, 3
37067 Valeggio sul Mincio (VR)

STULZCHSPL
(India) Pvt. Ltd.

006, Jagruti Industrial Estate
Mogul Lane, Mahim
Mumbai - 400 016

STULZ México S.A. de C.V.
Avda. Santa Fe No. 170
Oficina 2208, German Centre
Delegación Alvaro Obregon
MX- 01210 México
Distrito Federal

STULZ GROEP B. V.
Postbus 75
180 AB Amste lveen

STULZ New Zealand Ltd.
Office 71, 300 Richmond Rd.
Grey Lynn, Auckland

STULZ Polska SP. Z O.O.
Budynek Mistral.
Al. Jerozolimskie 162
02 – 342 Warszawa

STULZ Singapore Pte Ltd.
33 Ubi Ave 3 #0338 Vertex
Singapore 408868
[e-mail]

STULZ Air Technology and
Services Shanghai Co., Ltd.

Room 406, Building 5
457 North Shanxi Road
Shanghai 200040

STULZ South Africa Pty. Ltd.

Unit 3, Jan Smuts Business Park
Jet Park, Boksburg
Gauteng, South Africa

STULZ U. K. Ltd.
First Quarter,
Blenheim Rd. Epsom
Surrey KT 19 9 QN

OCC0207- April 2017 © STULZ USA – Specifi cations subject to change wtihout notice.

www.stulz-usa.com