Trane WSC060-120 User manual

Packaged Heat Pumps
Precedent™
WSC060-120
50 Hz
PKGP-PRC004-EN
February 2004

© 2003 American Standard Inc. All rights reserved. PKGP-PRC004-EN
Introduction
Precedent™…The same Trane
quality…with added flexibility.
Precedent is a flexible line of packaged
units that cover a wide variety of
applications.
ReliaTel™microprocessor controls
provide superior flexibility for the
simplest to the most sophisticated
applications. In addition to controls,
Precedent offers many other outstanding
features and option choices.
With its sleek compact cabinet, rounded
corners and beveled top, it may just be
the most aesthetically pleasing packaged
unit on the planet. And, of course,
Precedent carries the Trane reputation
for excellence, quality and reliability.
It’s
hard to stop a Trane .
From simple applications, to the most
complex, Precedent has the solution.

PKGP-PRC004-EN 3
Contents
Introduction
Features and Benefits
Application Considerations
Selection Procedure
Model Number Description
General Data
Performance Data
Controls
Electrical Data
Jobsite Connections
Dimensional Data
Weights
Mechanical Specifications
2
4
9
10
12
13
14
34
35
38
39
46
47

4PKGP-PRC004-EN
Features and
Benefits
Unit Cabinet
The compact cabinet with rounded
corners takes up less room and is less
costly to ship. The beveled and ribbed
top is not only aesthetically pleasing, it is
designed to prevent water from pooling
Single Point Power
A single electrical connection powers the
unit.
Unit Base
For added water integrity, Precedent has
a raised 29 mm 1(1/8") lip around the
unit’s downflow supply and return to
prevent water from blowing into the
ductwork.
Sloped Drain Pans
Every Precedent unit has a non-
corrossive, removable, double-sloped
drain pan that’s easy to clean and
reversible to allow installation of drain
trap on either side of the unit.
Through the Base Condensate
Every unit includes provisions for
through the base condensate drain
connections. This allows the drain to be
connected through the roof curb instead
of a roof penetration.
Foil-Faced Insulation
All panels in the Evaporator section of
the unit have cleanable foil-faced
insulation. All edges are either captured
or sealed to ensure no fibers get into the
airstream.
Easy-Adjust Idler Arm
With the Easy-Adjust Idler Arm, the belt
and sheaves can be quickly adjusted
without moving the mounted fan motor.
The result is a major savings in time and
money.
Patented Condenser Coil
Precedent boasts a patented 1+1+1
Hybrid coil, permanently gapped for
easy cleaning.
Colored And Numbered Wiring
You save time and money tracing wires
and diagnosing the unit.
Convertible Units
• The units ship in a downflow
configuration. They can be easily
converted to horizontal by simply
moving two panels.
• Units come complete with horizontal
duct flanges so the contractor doesn’t
have to field fabricate them. These duct
flanges are a time and cost saver.
Compressors
Precedent™contains the best compressor
technology available to achieve the
highest possible performance. Our
compressor line includes Trane-built
Climatuff™reciprocating and scrolls.
Easy Access Panels
Easy access panels reduce the number of
possible water entry points. Remove two
screws for access to the standardized
internal components and wiring.
Low Ambient Cooling
All Precedent units have cooling
capabilities down to -18°C (0°F) as
standard.

PKGP-PRC004-EN 5
Features and
Benefits
Flexible Applications
• Only two roof curbs for the 5-10 ton
Precedent line…simplifies curb
selection.
• Airflow is outstanding. The Precedent
can replace an older machine with old
ductwork and, in many cases, improve
comfort through better air distribution.
• Belt drive — standard or oversized
supply fan motors meet a wide airflow
range.
• Precedent offers ultimate flexibility.
Options and components are not pre-
packaged at the factory. Units are built
to order in our standard “shortest in
the industry” ship cycle time.
Standardized Components
• Components are placed in the same
location on all Precedent™units.
Familiarize yourself with one Precedent
and you are familiar with every
Precedent.
Easy Access Low Voltage Terminal
Board
Precedent’s Low Voltage Terminal Board
is external to the electrical control
cabinet. It is extremely easy to locate and
attach the thermostat wire. This is
another cost and time saving installation
feature.
Low Voltage Connections
The wiring of the low voltage
connections to the unit and the zone
sensors is as simple as 1-1, 2-2, and 3-3.
This simplified system makes it easy for
the installer to wire
Single-Side Service
Single-side service is standard on all
Precedent units.

6PKGP-PRC004-EN
Features and
Benefits
Micro Controls
Several years ago, Trane was the first to
introduce microprocessor controls into
the Light Commercial Market. That
design, along with immeasurable
experience, has provided the technology
for Trane’s second-generation ReliaTel™
microprocessor controls.
ReliaTel Micro:
• Provides unit control for heating,
cooling, and ventilating by utilizing
input from sensors that measure
outdoor and indoor temperature.
• Improves quality and reliability through
the use of time-tested microprocessor
controls and logic.
• Prevents the unit from short cycling,
considerably improving compressor
life.
• Ensures that the compressor will run
for a specific amount of time, which
allows oil to return for better
lubrication, enhancing the reliability of
the compressor.
• Reduces the number of components
required to operate the unit, thereby
reducing possibilities for component
failure.
• Eliminates the need for field-installed
components with its built-in anti-
short-cycle timer, time delay relay
and minimum ‘’on’’ time controls.
These controls are factory tested to
assure proper operation.
• Requires no special tools to run the
Precedent unit through its paces
during testing. Simply place a
jumper between Test 1 and Test 2
terminals on the Low Voltage
Terminal Board and the unit will walk
through its operational steps. The
unit automatically returns control to
the zone sensor after stepping
through the test mode a single time,
even if the jumper is left on the unit.
• As long as the unit has power and
the LED is lit, the Micro is
operational. The light indicates that
the Micro is functioning properly.
• Features expanded diagnostic
capabilities when used with Trane’s
Integrated Comfort ™ systems.
• As an energy benefit, softens
electrical ‘’spikes’’ by staging on fans,
compressors and heaters.
• The Intelligent Fallback or Adaptive
Control is a benefit to the building
occupant. If a component goes
astray, the unit will continue to
operate at predetermined
temperature set points.
• Intelligent Anticipation is a standard
feature of the Micro. Functioning
constantly, the Micro and zone
sensors work together in harmony to
provide tight comfort control.

PKGP-PRC004-EN 7
Factory-installed Options
Hinged Access Doors
These doors permit easy access to the
filter, fan/heat, and compressor/control
sections. They reduce the potential roof
damage from screws or sharp access
door corners.
Economizer
Equipped with either dry bulb, reference
or comparative enthalpy sensing, this
feature provides free cooling as the
outdoor temperature and/or humidity
decreases. Economizers, correctly
installed, offer valuable energy savings.
Factory-installed economizers save time
and ensure proper installation.
Phase Monitor
Phase monitor shall provide 100%
protection for motors and compressors
against problems caused by phase loss,
phase imbalance, and phase reversal.
Phase monitor is equipped with an LED
that provides an ON or FAULT indicator.
Clogged Filter/Fan Fail Switches
These sensors allows a zone sensor
service light or Integrated Comfort
system to indicate a dirty filter or a fan
that’s not working. The field installation
charges for these valuable feedback
devices often eliminate them from
consideration. Factory installation can
make such features a good investment.
Comm-3/4Trane Communication
Interface
Available factory or field-installed.This
module, when applied with the Micro,
easily interfaces withTrane’s Integrated
Comfort™ system.
The following options round-out the
complete line of Precedent™options:
— 0 - 50% Manual or Motorized
Outside Air
— Discharge Air Sensor
— Electric heaters (available as field-
installed accessories)
— Hail Protection Quality Coil
Guards
— Wide array of Zone Sensors
— Factory built Roof Curb
One of Our Finest Assets:
Trane Sales Representatives are a
Support group that can assist you
with:
— Product
— Application
— Service
— Training
— Special Applications
— Specifications
— Computer Programs and much
more
Precedent has the features and
benefits that make it first class in the
light commercial rooftop market.
Designed with input from field
contractors and engineers, its airflow
performance is outstanding.
Precedent…The same Trane
quality…with added flexibility.
Features and
Benefits

8PKGP-PRC004-EN
Features and
Benefits
VariTrac™
VariTrac
When Trane’s changeover VAV System
for light commercial applications is
coupled with Precedent, it provides the
latest in technological advances for
comfort management systems and can
allow thermostat control in every zone
served by VariTrac.
• We perform a 100% coil leak test at the
factory. The evaporator and condenser
coils are leak tested at 1,375 kPa (200
psig) and pressure tested to 3,100 kPa
(450 psig).
• All parts are inspected at the point of
final assembly. Sub-standard parts are
identified and rejected immediately.
• Every unit receives a 100% unit run test
before leaving the production line to
make sure it lives up to rigorous Trane
requirements.
We test designs at our factory not on
our customers!
Quality And Reliability Testing
• All Precedent™designs were rigorously
rain tested at the factory to ensure
water integrity.
• Actual shipping tests were performed
to determine packaging requirements.
Units were test shipped around the
country to determine the best
packaging.
• Factory shake and drop tests were
used as part of the package design
process to help assure that the unit
arrives at the job site in top condition.
• Rigging tests include lifting a unit into
the air and letting it drop one foot,
assuring that the lifting lugs and rails
hold up under stress.

PKGP-PRC004-EN 9
Application of this product should be
within the cataloged airflow and cooling
considerations.
Low Ambient Cooling
Precedent™ features, as standard, low
ambient cooling down to -18°C (0°F).
Contact your local Trane Representative
for more assistance with low ambient
cooling applications.
Barometric Relief
This product line offers an optional
barometric relief damper for use in
conjunction with economizer option.
This option consists of gravity dampers
which open with increased pressure. As
the building air pressure increases, the
pressure in the unit return air section
also increases, opening the dampers
and relieving the conditioned space.
NOTE: THE EFFECTIVENESS OF
BAROMETRIC RELIEF DAMPER
DURING ECONOMIZING OPERATION
IS SYSTEM RELATED.
PRESSURE DROP OF THE RETURN AIR
SYSTEM SHOULD BE CONSIDERED TO
CONTROL BUILDING PRESSURIZA-
TION.
Condensate Trap
The evaporator is a draw-thru
configuration. A trap must be field
provided prior to start-up on the cooling
cycle.
Clearance Requirements
The recommended clearances identified
with unit dimensions should be
maintained to assure adequate service,
maximum capacity and peak operating
efficiency. Actual clearances which
appear inadequate should be reviewed
with the local Trane sales personnel.
Unit Pitch
These units have reversible sloped
condensate drain pans. Units must be
installed level, any unit slope must be
toward side of unit where condensate
drain is connected.
Application
Considerations

10 PKGP-PRC004-EN
Selection
Procedure - SI Units
Cooling Capacity
Step 1
Calculate the building’s total and
sensible cooling loads at design
conditions. Use the Trane calculation
form or any other standard accepted
method.
Step 2
Size the equipment using Table PD-1.
Match the cooling loads at design
conditions.
Example: The following are the building
cooling requirements:
A
Electrical Characteristics: 380–415/50/3
B
Summer Design Conditions:
Entering Evaporator Coil: 27 DB/ 19 WB
Outdoor Ambient: 35
C
Total Cooling Load: 17.0 kW
D
Sensible Cooling Load: 11.7 kW
E
Airflow: 3,400 m3/hr
External Static Pressure: 130 Pa
F
Downflow Configuration
Table PD-1 shows that a WSC060AD has
a gross cooling capacity of 18.1 kW and
14.7 kW sensible capacity at 35 degree C
ambient and 3,400 m3/hr with 27 DB/19
WB air entering the evaporator.
To find the net cooling capacities, fan
motor heat must be subtracted.
Determine the total unit static pressure:
External Static 130 Pa
Standard Filter 1 in. 37 Pa
Economizer 46 Pa
Supplementary Electric Heat 21 Pa
Total Static Pressure 234 Pa
Note: The Evaporator Fan Performance
Table PD-9 has deducted the pressure
drop for a 25 mm filter already in the
downflow unit.
Therefore, the actual Total Static
Pressure is 234 – 37 = 197 Pa. With 3,400
m3/hr and 197 Pa,Table PD-9 shows 0.75
kW.
Note below the table gives a formula to
calculate Fan Motor Heat,
Fan Motor Heat (kW) =
1.144 x (Fan kW) + 0.132
= 1.144 x 0.75 + 0.132 = 1.0 kW
Net Total Cooling Capacity =
18.1 – 1.0 = 17.1 kW
Net Sensible Cooling Capacity =
14.7 – 1.0 = 13.7 kW
Heating Capacity
Step 1
Calculate the building heating load using
the Trane calculation form or other
standard accepted method.
Step 2
Size the equipment usingTable PD-5 to
match the heating loads at design
conditions.
A
Total Heating Load: 16 kW
B
Outdoor Ambient (Winter) –9°C DB
C
Indoor Return Temperature: 21°C DB
D
Airflow: 3,400 m3/hr
Use the portion ofTable PD-5 for the
WSC060AD to determine capacity at
winter design conditions. The
mechanical heating portion of the heat
pump will provide 8.3 kW.
Step 3
Because 8.3 kW is less than the
building’s required heating capacity at
winter design conditions, a
supplementary heater must be selected.
16 kW – 8.3 kW = 7.7 kW
FromTable PD-9, at 380 volts, the 10.9
kW Heater will be adequate to do the
job.
10.9 kW 38.0 MBh
From Table ED-5 select heater
BAYHTRR418A (10.9 kW 380/50/3).
Air Delivery Selection
External static pressure drop through the
air distribution system has been
calculated to be 200 Pa. EnterTable PD-9
for a WSC060AD at 3400 m3/h and 200
Pa static pressure. The standard motor
will give the desired airflow.
Accessory Selection
Select accessories needed to
accommodate the application.