Packaged Rooftop Air Conditioners
Voyager™ Commercial with ReliaTel™Controls
27½ to 50 Tons - 60 Hz
22.9 to 41.7 Tons (81-148 kW) - 50 Hz
May 2014RT-PRC033F-EN
Introduction
Packaged Rooftop Air Conditioners
Through the years, Trane has designed and developed the most complete line of Packaged Rooftop
products available in the market today. Trane was the first to introduce the Micro—microelectronic
unit controls—and has continued to improve and revolutionize this design concept.
The ReliaTel™ control platform offers the same great features and functionality as the original
Micro, with additional benefits for greater application flexibility.
The Voyager™ Commercial line offers 27½ to 50 ton, 60 Hz and 23 to 42 ton 50 Hz models. Both
50 and 60 Hz models come in a choice of five sizes to meet the changing demands of the commercial
rooftop market.
Trane customers demand products that provide exceptional reliability, meet stringent performance
requirements, and are competitively priced. Trane delivers with Voyager Commercial.
Voyager Commercial features cutting edge technologies: reliable 3-D™ Scroll compressors, eStage
for premium efficiency, Trane engineered ReliaTel controls, computer-aided run testing, and
Integrated Comfort™ Systems.
So, whether you’re a contractor, the engineer, or an owner you can be certain Voyager Commercial
Products are built to meet your needs.
It’s Hard To Stop A Trane.®
Revision Summary
RT-PRC033F-EN (05 May 2014)
•Added Low Leak Damper option, eStage, Ultra Low Leak Power Exhaust, Touchscreen Human
Interface.
•Updated Features and Benefits, General Data, Model Number Description, Performance Data,
Controls, Dimensional Data, Electrical Data, Mechanical Specifications.
sensors for space comfort control (SCC) or discharge air control (DAC)
2
Quality and Reliability
Easy to Install, Service and Maintain
Because today’s owners are very cost-conscious when it comes to service and maintenance, the
Trane Voyager was designed with direct input from service contractors. This valuable information
helped to design a product that would get the service technician off the job quicker and save the
owner money.
Rigorous Testing
All of Voyager’s designs were rigorously rain tested at the factory to ensure water integrity. Actual
shipping tests are performed to determine packaging requirements. Units are test shipped around
the country. Factory shake and drop tested as part of the package design process to help assure
that the unit will arrive at your job site in top condition.
RT-PRC033F-EN7
Features and Benefits
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. 100% coil leak test is performed at the factory. The evaporator
coil is pressure tested to 450 psig and the condenser coil at 650 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.
ReliaTel™ Controls
ReliaTel controls provide unit control for heating, cooling and ventilating utilizing input from
sensors that measure outdoor and indoor temperature.
Quality and Reliability are enhanced through ReliaTel control 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
Voyager with ReliaTel reduces the number of components required to operate the unit, thereby
reducing possibilities for component failure.
ReliaTel Makes Installing and Servicing Easy
ReliaTel eliminates the need for field installed anti-shortcycle timer and time delay relays. ReliaTel
controls provide these functions as an integral part of the unit. The contractor no longer has to
purchase these controls as options and pay to install them.
The wiring of the low voltage connections to the unit and the zone sensors is as easy as 1-1, 2-2,
and 3-3. This simplified system makes it easier for the installer to wire.
for better lubrication, enhancing the reliability of the commercial compressor.
ReliaTel Makes Testing Easy
ReliaTel requires no special tools to run the Voyager unit through its paces. 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 automatically.
Note: 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 “system on” LED is lit, ReliaTel is operational. The light
indicates that the controls are functioning properly. ReliaTel features expanded diagnostic
capabilities when utilized with Trane Integrated Comfort™ Systems. Some zone sensor options
have central control panel lights which indicate the mode the unit is in and possible diagnostic
information (dirty filters for example).
Other ReliaTel Benefits
The ReliaTel’s built-in anti-shortcycle timer, time delay relay and minimum “on” time control
functions are factory tested to assure proper operation. ReliaTel softens electrical “spikes” by
staging on fans, compressors and heaters. Intelligent Fallback is a benefit to the building occupant.
If a component goes astray, the unit will continue to operate at predetermined temperature
setpoint.
Intelligent Anticipation is a standard ReliaTel feature. It functions continuously as ReliaTel and zone
sensor(s) work together in harmony to provide much tighter comfort control than conventional
electro-mechanical thermostats.
8 RT-PRC033F-EN
Human Interface
Forced Combustion Blower
Negative Pressure
Gas Valve
Hot Surface Ignitor
The 5 Inch Color Touchscreen Human Interface provides
an intuitive user interface to the rooftop unit that speeds
up unit commissioning, shortens unit troubleshooting
times, and enhances preventative maintenance
measures. The human interface includes several
features such as:
•Data trending capabilities by means of time series
graphs
•Historical alarm messages
•Real-time sensor measurements
•On board system setpoints
•USB port that enables the downloading of
component runtime information as well as trended
historical sensor data
•Customized reports
Note: For more information, refer to Tracer™ TD-5 literature, RT-SVX49*-EN.
Conversionless Units
Features and Benefits
Drum and Tube Heat Exchanger (Gas Heat Only)
The dedicated downflow, horizontal or mixed airflow configurations require no panel removal or
alteration time to convert in the field — a major cost savings during installation.
The drum and tube heat exchanger is designed for increased efficiency and reliability and utilizes
the same technology that has been incorporated into large commercial roof top units for over 20
years.
The heat exchanger is manufactured using optional stainless, or standard aluminized, steel with
stainless steel components for maximum durability. The requirement for cycle testing of heat
exchangers is 10,000 cycles by ANSI Z21.47. This is the standard require d by both cULus and AGA
for cycle test requirements. Trane requires the design to be tested to 2½ times this current standard.
The drum and tube design has been tested and passed over 150,000 cycles which is over 15 times
the current ANSI cycling requirements.
The regulated gas valve will not allow gas flow unless the combustion blower is operating. This
is one of the unique safety features of Voyager Commercial. The forced combustion blower
RT-PRC033F-EN9
Features and Benefits
supplies pre-mixed fuel through a single stainless steel burner screen into a sealed drum where
ignition takes place. It is more reliable to operate and maintain than a multiple burner system.
The hot surface ignitor is a gas ignition device which doubles as a safety device utilizing a
continuous test to prove the flame. The design is cycle tested at the factory for quality and
reliability.
All the gas/electric rooftops exceed all California seasonal efficiency requirements. They also
perform better than required to meet the California NOx emission requirements.
Low Ambient Cooling
All Voyager Commercial units have cooling capabilities down to 0°F as standard.
Microchannel Condenser Coils
Due to flat streamlined tubes with small ports,
and metallurgical tube-to-fin bond,
microchannel coil has better heat transfer
performance.
Microchannel condenser coil can reduce
system refrigerant charge by up to 50%
because of smaller internal volume, which
leads to better compressor reliability. Compact
all-aluminum microchannel coils also help to
reduce the unit weight.
All-aluminum construction improves recyclability. Galvanic corrosion is also
minimized due to all-aluminum construction.
Strong aluminum brazed structure provides
better fin protection. In addition, flat
streamlined tubes also make microchannel
coils more dust resistant and easier to clean.
Phase Monitor
Voyager features a three-phase line monitor module that protects against phase loss, phase
reversal and phase unbalance. It is intended to protect compressors from reverse rotation. It has
an operating input voltage range of 190–600 Vac, and LED indicators for ON and FAULT. There are
no field adjustments and the module will automatically reset from a fault condition.
Pressure Cutouts
Low and high pressure cutouts are standard on all models.
Single Point Power
A single electrical connection powers the unit.
Sloped Drain Pans
Every unit has a non-corrosive, sloped drain pan made of pre-painted steel and standard on all
units.
Temperature Discharge Limit (TDL)
A bi-metal element discharge line thermostats is installed as a standard feature on the discharge
line of each system. This standard option provides extra protection to the compressors against high
discharge temperatures in case of loss of charge, extremely high ambient and other conditions
which could drive the discharge temperature higher.
10 RT-PRC033F-EN
Features and Benefits
Outstanding Optional Features
Variable Frequency Drives (VFD)
Variable Frequency Drives are factory installed and tested to provide supply fan motor speed
modulation, as well as modulating gas heat. VFD’s on the supply fan, as compared to inlet guide
vanes or discharge dampers, are quieter, more efficient, and are eligible for utility rebates. The
VFD’s are available with or without a bypass option. Bypass control will simply provide full nominal
airflow in the event of drive failure.
Modulating gas heat models with VFD's allow tighter space temperature control with less
temperature swing.
Single Zone VAV – An Ideal Energy Saving Solution for Yesterday’s “Constant Volume”
Systems
Single zone VAV is designed for use in single zone applications like gymnasiums, auditoriums,
manufacturing facilities, retail box stores, and any large open spaces, where there is a lot of
diversity in the load profile. Single Zone VAV (SZ VAV) is an ideal replacement to “yesterday’s”
constant volume (CV) systems, by reducing operating costs while improving occupant comfort.
SZ VAV systems combine Trane application, control and system integration knowledge to exactly
match fan speed with cooling and heating loads, regardless of the operating condition. Trane
algorithms meet/exceed ASHRAE 90.1- 2010, SZ VAV energy-saving recommendations, and those
of CA Title 24. The result is an optimized balance between zone temperature control and system
energy savings. Depending on your specific application, energy savings can be as much as 20+%.
Note: Building system modeling in energy simulation software like TRACE is recommended to
evaluate performance improvements for your application.
SZ VAV is fully integrated into the ReliaTel Control system and is available today. It provides the
simplest and fastest commissioning in the industry through proven factory-installed, wired, and
tested system controllers. All control modules, logic and sensors are factory installed, and tested
to assure the highest quality and most reliable system available. This means no special
programming of algorithms, or hunting at the jobsite for sensors, boards, etc. that need to be
installed in the field. Single zone VAV is a quick and simple solution for many applications and is
available from your most trusted rooftop VAV system solution provider- Trane.
Delivered VAV
Trane provides true pressure independent variable air volume with Voyager Commercial delivered
VAV. The system is auto-configured to reduce programming and set-up time on the job. Generally
available only on sophisticated larger models, this Voyager Commercial system can economically
handle comfort requirements for any zone in the facility.
The system consists of:
•Voyager™ Commercial VAV packaged rooftops
•Up to 32 VariTrane™ VAV boxes with DDC (direct digital controls)
•VariTrac™ Central Control Panel (CCP) with Operator Display (OD)
The VariTrac Central Control Panel acts as a communications hub by coordinating the actions of
the VAV rooftop and the VAV boxes. Single duct or fan powered VAV boxes are available, along with
an option for factory-installed local heat. For more details, see VAV-SLM003-EN.
RT-PRC033F-EN11
Features and Benefits
VariTrac™ Changeover-Bypass VAV
Power Exhaust Option
For large commercial applications, Trane offers constant
volume (CV) Voyager Commercial models with a
changeover-bypass VAV system. For the most advanced
comfort management systems, count on Trane.
Provides exhaust of the return air when using an economizer to
maintain proper building pressurization. Great for relieving most
building overpressurization problems.
Fresh Air Tracking Power Exhaust Option
Provides exhaust of the return air to maintain proper building pressurization by proportionally
controlling the exhaust air to the economizer dampers; in other words, the exhaust damper
“tracks” the outside air damper position.
Statitrac™ Direct Space Building Pressurization Control
Trane's Statitrac™ control is a highly accurate and efficient method of maintaining building
pressure control with a large rooftop air conditioner. Statitrac space pressure control turns the
exhaust fans on and modulates exhaust dampers to maintain space pressure within the space
pressure deadband. Proper building pressurization eliminates annoying door whistling, doors
standing open, and odors from other zones.
Downflow and Horizontal Economizers
The economizers come with three control options:
dry bulb, enthalpy and differential enthalpy. The
photo shows the three fresh air hoods on the
horizontal discharge configuration.
12 RT-PRC033F-EN
Trane Air Quality (Traq™) Outside Air Measurement System
Trane Air Quality (Traq) outside air measurement system uses velocity pressure sensing rings to
measure airflow in the outside air opening from 40 cfm/ton to maximum airflow. Measurement
accuracy is at least ±15%, meeting requirements of LEED IE Q Credit 1.
Interoperability with BACnet (BCI-R)
The Trane BACnet Control Interface (BCI-R) for Voyager Commercial offers a building automation
control system with outstanding interoperability benefits. BACnet, which is an industry standard,
is an open, secure and reliable network communication protocol for controls, created by American
Society of Heating, refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE).
Interoperability allows application or project engineers to specify the best products of a given type,
rather than one individual supplier's entire system. It reduces product training and installation
costs by standardizing communications across products. Interoperable systems allow building
managers to monitor and control IntelliPak equipment with Tracer SC controls or a 3
building automation system. It enables integration with many different building controls such as
access/intrusion monitoring, lighting, fire and smoke devices, energy management, and a wide
variety of sensors (temperature, pressure, light, humidity, occupancy, CO
Interoperability with LonTalk® (LCI-R)
The LonTalk Communication (LCI-R) for Voyager Commercial offers a building automation control
system with outstanding interoperability benefits. LonTalk, which is an industry standard, is an
open, secure and reliable network communication protocol for controls, created by Echelon
Corporation and adopted by the LonMark Interoperability Association. It has been adopted by
several standards, such as: EIA-709.1, the Electronic Industries Alliance (EIA) Control Network
Protocol Specification and ANSI/ASHRAE 135, part of the American Society of Heating,
Refrigeration, and Air-Conditioning Engineer’s BACnet control standard for buildings.
Interoperability allows application or project engineers to specify the best products of a given type,
rather than one individual supplier’s entire system. It reduces product training and installation
costs by standardizing communications across products.
Interoperable systems allow building managers to monitor and control Voyager Commercial
equipment with a Trane Tracer Summit™ or a 3
It enables integration with many different building controls such as access/intrusion monitoring,
lighting, fire and smoke devices, energy management, and a wide variety of sensors for
temperature, pressure, humidity and occupancy CO
www.lonmark.org or Echelon, www.echelon.com.
rd
party building automation system.
. For additional information visit LonMark,
2
Features and Benefits
rd
party
and air velocity).
2
Trane Communication Interface (TCI)
The TCI is available factory or field installed. When applied with ReliaTel, this module easily
interfaces with the Trane Integrated Comfort™ System.
Trane Wireless Comm Interface (WCI)
The Trane® Wireless Comm Interface (WCI) is the perfect alternative to Trane’s BACnet™ wired
communication links (for example, Comm links between a Tracer™ SC and a Tracer UC400).
Minimizing communication wire use between terminal products, zone sensors, and system
controllers has substantial benefits. Installation time and associated risks are reduced. Projects are
completed with fewer disruptions. Future re-configurations, expansions, and upgrades are easier
and more cost effective.
Modulating Hot Gas Reheat
This option allows for increased outdoor air ventilation. It reduces humidity levels while increasing
comfort level in the air space. Cooling can operate without a demand for dehumidification. The hot
gas reheat coil and modulating valve are designed to deliver maximum reheat temperatures and
RT-PRC033F-EN13
Features and Benefits
increase unit efficiency. This energy efficiency helps to meet local energy codes and ASHRAE
Standard 90.1 compliance.
Figure 1. Modulating hot gas reheat option
Tool-Less Condenser Hail Guards
Tool-less condenser hail guards are available as a factory installed option to protect the unit
condenser coil from hail, debris damage and vandalism.
Trane Factory Built Roof Curbs
Available for all units.
Motor Shaft Grounding Ring
Motors with internal Shaft grounding rings can be used with VFDs to provide a conductive
discharge path away from the motor bearings to ground.
Condensate Overflow Switch
A condensate overflow switch is available to shut the unit down in the event that the condensate
drain becomes clogged. This option protects the unit from water overflowing from the drain pan
and entering the base of the unit.
eStage - High Efficiency Units
Through compressor staging on a single circuit, this option allows units to have a maximum 25%
load at the first stage allowing the unit to meet Title 24, along with providing increased full load
and part load unit efficiency.
One of Our Finest Assets
Trane Commercial Sales Engineers are a support group that can assist you with:
•Product•Special Applications
•Application•Specifications
•Service•Computer Programs and more
•Training
14 RT-PRC033F-EN
Application Considerations
60/50 Hz Units
Exhaust Air Options
When is it necessary to provide building exhaust?
Whenever an outdoor air economizer is used, a building generally requires an exhaust system. The
purpose of the exhaust system is to exhaust the proper amount of air to prevent over or underpressurization of the building.
A building may have all or part of its exhaust system in the rooftop unit. Often, a building provides
exhaust external to the air conditioning equipment. This external exhaust must be considered
when selecting the rooftop exhaust system.
Voyager™ Commercial rooftop units offer four types of exhaust systems:
1. 50% or 100% Power exhaust fan
2. 50% or 100% Fresh Air Tracking Power Exhaust Fan(s)
3. 100% Power Exhaust with Statitrac™ Building Pressure Control
4. Barometric relief dampers
Application Recommendations
Power Exhaust Fan (with or without Fresh Air Tracking)
The exhaust fan option is either a single fan for exhausting approximately half of the air-moving
capabilities of the supply fan system or dual fans for 100% exhaust. Either exhaust capability
arrangement is configured as an on/off non-modulating exhaust or an on/off exhaust with an
actuator controlled damper to track the position of the fresh air damper.
For non-100% air applications, the 50% non-tracking power exhaust fan generally should not be
selected for more than 40 to 50% of design supply airflow. Since it is an on/off non-modulating fan,
it does not vary exhaust cfm with the amount of outside air entering the building. Therefore, if
selected for more than 40 to 50% of supply airflow, the building may become under pressurized
when economizer operation is allowing lesser amounts of outdoor air into the building. If, however,
building pressure is not of a critical nature, the non-modulating exhaust fan may be sized for more
than 50% of design supply airflow. Consult Table 28, p. 59 and Table 29, p. 59 (60Hz) or Ta b le 6 0 ,
p. 87 and Table 61, p. 88 (50Hz) for specific exhaust fan capabilities with Voyager Commercial units.
100% Power Exhaust with Statitrac™ Building Pressure Control
This control is available only with 100% power exhaust. The exhaust dampers are modulated in
response to building pressure. Statitrac, a differential pressure control system, uses a differential
pressure transducer to compare indoor building pressure to atmospheric pressure. The exhaust
fans are turned on when required to lower building static pressure to setpoint. The Statitrac control
system then modulates the exhaust dampers to control the building pressure to within the
adjustable, specified deadband that is set at the RTVM board. Economizer and return air dampers
are modulated independent of the exhaust dampers based on ventilation control and economizer
cooling requests.
Statitrac can only lower building pressure; it cannot raise it. To lower building pressure, Statitrac
exhausts air from the space using the power exhaust. To raise building pressure, more air must be
supplied to the space, as with economizer operation. Additional relief, such as a bathroom exhaust
fan or relief fan, as well as other units serving the space, will affect building pressure and must be
taken into account.
Barometric Relief Dampers
Barometric relief dampers consist of gravity dampers which open with increased building
pressure. As the building pressure increases, the pressure in the unit return section also increases,
RT-PRC033F-EN15
Application Considerations
opening the dampers and relieving air. Barometric relief may be used to provide relief for single
story buildings with no return ductwork and exhaust requirements less than 25%.
Altitude Corrections
The rooftop performance tables and curves of this catalog are based on standard air (.075 lbs/ft).
If the rooftop airflow requirements are at other than standard conditions (sea level), an air density
correction is needed to project accurate unit performance.
Figure 3, p. 42 shows the air density ratio at various temperatures and elevations. Trane rooftops
are designed to operate between 40° and 90°F leaving air temperature.
The procedure to use when selecting a supply or exhaust fan on a rooftop for elevations and
temperatures other than standard is as follows:
1. First, determine the air density ratio using Figure 3, p. 42.
2. Divide the static pressure at the nonstandard condition by the air density ratio to obtain the
corrected static pressure.
3. Use the actual cfm and the corrected static pressure to determine the fan rpm and bhp from the
rooftop performance tables or curves.
4. The fan rpm is correct as selected.
5. Bhp must be multiplied by the air density ratio to obtain the actual operating bhp.
In order to better illustrate this procedure, the following examples are used:
60 Hz
Consider a 30 ton rooftop unit that is to deliver 11,000 actual cfm at 1.50 inches total static pressure
(tsp), 55°F leaving air temperature, at an elevation of 5,000 ft.
1. Fr om Figure 3, p. 42, the air density ratio is 0.86.
2. Tsp=1.50 inches/0.86=1.74 inches tsp.
3. From the performance tables: a 30 ton rooftop will deliver 11,000 cfm at 1.74 inches tsp at
632 rpm and 6.2 bhp.
4. The rpm is correct as selected — 632 rpm.
5. Bhp = 6.2 x 0.86 = 5.33.
Compressor MBh, SHR, and kW should be calculated at standard and then converted to actual
using the correction factors in Tab le 9, p. 42 . Apply these factors to the capacities selected at
standard cfm so as to correct for the reduced mass flow rate across the condenser.
Heat selections other than gas heat will not be affected by altitude. Nominal gas capacity (output)
should be multiplied by the factors given in Table 10, p. 42 before calculating the heating supply
air temperature.
50 Hz
Consider a 29 ton (105 kW) rooftop unit that is to deliver 9,160 actual cfm (4323 L/s) at 1.50 inches
total static pressure (tsp) (38 mm, 373 Pa), 55°F (12.8°C) leaving air temperature, at an elevation of
5,000 ft (1524 m).
1. Fr om Figure 3, p. 42, the air density ratio is 0.86.
3. From the performance tables: a 29-ton (105 kW) rooftop will deliver 9,160 cfm at 1.74 inches tsp
(4323 L/s at 434 Pa) at 618 rpm and 4.96 bhp (3.7 kW).
4. The rpm is correct as selected – 618 rpm.
5. Bhp = 4.96 x 0.86 = 4.27 bhp actual. kW = 3.7 x 0.86 = 3.18 kW
16 RT-PRC033F-EN
Compressor MBh, SHR, and kW should be calculated at standard and then converted to actual
using the correction factors in Tab le 9, p. 42 . Apply these factors to the capacities selected at
standard cfm so as to correct for the reduced mass flow rate across the condenser.
Heat selections other than gas heat will not be affected by altitude. Nominal gas capacity (output)
should be multiplied by the factors given in Table 10, p. 42 before calculating the heating supply
air temperature.
Acoustical Considerations
Proper placement of rooftops is critical to reducing transmitted sound levels to the building. The
ideal time to make provisions to reduce sound transmissions is during the design phase. The most
economical means of avoiding an acoustical problem is to place the rooftop(s) away from
acoustically critical areas. If possible, rooftops should not be located directly above areas such as:
offices, conference rooms, executive office areas and classrooms. Instead, ideal locations might be
over corridors, utility rooms, toilets or other areas where higher sound levels directly below the
unit(s) are acceptable.
Several basic guidelines for unit placement should be followed to minimize sound transmission
through the building structure:
1. Never cantilever the compressor end of the unit. A structural cross member must support this
end of the unit.
2. Locate the unit center of gravity which is close to, or over, a column or main support beam.
3. If the roof structure is very light, roof joists must be replaced by a structural shape in the critical
areas described above.
4. If several units are to be placed on one span, they should be staggered to reduce deflection over
that span.
It is impossible to totally quantify the effect of building structure on sound transmission, since this
depends on the response of the roof and building members to the sound and vibration of the unit
components. However, the guidelines listed above are experience- proven guidelines which will
help reduce sound transmissions.
Application Considerations
Clearance Requirements
The recommended clearances identified with unit dimensions should be maintained to assure
adequate serviceability, maximum capacity and peak operating efficiency. A reduction in unit
clearance could result in condenser coil starvation or warm condenser air recirculation. If the
clearances shown are not possible on a particular job, consider the following:
Do the clearances available allow for major service work such as changing compressors or coils?
Do the clearances available allow for proper outside air intake, exhaust air removal and condenser
airflow?
If screening around the unit is being used, is there a possibility of air recirculation from the exhaust
to the outside air intake or from condenser exhaust to condenser intake?
Actual clearances which appear inadequate should be reviewed with a local Trane sales engineer.
When two or more units are to be placed side by side, the distance between the units should be
increased to 150% of the recommended single unit clearance. The units should also be staggered
for two reasons:
1. To reduce span deflection if more than one unit is placed on a single span. Reducing deflection
discourages sound transmission.
2. To assure proper diffusion of exhaust air before contact with the outside air intake of adjacent
unit.
RT-PRC033F-EN17
Application Considerations
Duct Design
It is important to note that the rated capacities of the rooftop can be met only if the rooftop is
properly installed in the field. A well designed duct system is essential in meeting these capacities.
The satisfactory distribution of air throughout the system requires that there be an unrestricted and
uniform airflow from the rooftop discharge duct. This discharge section should be straight for at
least several duct diameters to allow the conversion of fan energy from velocity pressure to static
pressure.
When job conditions dictate elbows be installed near the rooftop outlet, the loss of capacity and
static pressure may be reduced through proper direction of the bend in the elbow. The high velocity
side of the rooftop outlet should be directed at the outside radius of the elbow rather than the
inside.
18 RT-PRC033F-EN
Selection Procedure
60 Hz Units
Five Basic Areas
1. Cooling capacity
2. Heating capacity
3. Air delivery
4. Unit electrical requirements
5. Unit designation
Cooling Capacity Selection
1. Summer design conditions — 95 DB/76 WB, 95°F entering air to condenser.
2. Summer room design conditions — 76 DB/66 WB.
3. Total peak cooling load — 321 MBh (26.75 tons).
4. Total peak supply cfm — 12000 cfm.
5. External static pressure — 1.2 inches.
6. Return air temperatures — 80 DB/66 WB.
7. Return air cfm — 10800 cfm.
8. Outside air ventilation cfm and load — 1200 cfm and 18.23 MBh (1.52 tons).
9. Unit accessories include:
a. Aluminized heat exchanger — high heat module.
b. 2” Hi-efficiency throwaway filters.
c. Economizer.
Step 1. A summation of the peak cooling load and the outside air ventilation load shows: 26.75
tons + 1.52 tons = 28.27 required unit capacity. From Table 13, p. 45, 30-ton unit capacity at
80 DB/67 WB, 95°F entering the condenser and 12,00 0 total peak supply cfm, is 353 MBh (29.4 tons).
Thus, a nominal 30 ton unit is selected.
Step 2. Having selected a nominal 30 ton unit, the supply fan and exhaust fan motor bhp must
be determined.
Supply Air Fan
Determine unit static pressure at design supply cfm (see Table 26, p. 57):
External static pressure = 1.20 inches
Heat exchanger = High Heat: 0.14 inches
High efficiency filter 2”= 0.23 inches
Indoor coil = 0.34 inches
Economizer = 0.07 inches
Unit total static pressure = 1.98 inches
Using total cfm of 12000 and total static pressure of 1.98 inches, Table 24, p. 54 shows 7.78 bhp with
676 rpm.
Step 3. Determine evaporator coil entering air conditions. Mixed air dry bulb temperature
determination.
Using the minimum percent of OA (1,200 cfm ÷ 12,000 cfm = 10 percent), determine the mixture
dry bulb to the evaporator. RADB +%OA (OADB - RADB) = 80 + (0.10) (95 - 80) = 80 + 1.5 = 81.5°F
RT-PRC033F-EN19
Selection Procedure
Approximate Wet Bulb Mixture Temperature
RAWB + OA (OAWB - RAWB) = 66 + (0.10) (76-66) = 68 + 1 = 67°F. A psychrometric chart can be used
to more accurately determine the mixture temperature to the evaporator coil.
Step 4.
Determine Total Required Unit Cooling Capacity
Required capacity = total peak load + O.A. load + supply air fan motor heat. From Figure 2, p. 22,
the supply air fan motor heat for 7.78 bhp = 22.1 MBh. Capacity = 321 + 18.23 + 22.1 = 361.3 MBh
(30.1 tons)
Step 5.
Determine Unit Capacity
From Table 13, p. 45 unit capacity at 81.5 DB. 67 WB entering the evaporator, 12000 supply air cfm,
95°F entering the condenser is 355 MBh (29.6 tons) 290 sensible MBh.
Step 6.
Determine Leaving Air Temperature
Unit sensible heat capacity, corrected for supply air fan motor heat 290 - 22.1 = 267.9 MBh.
Supply air dry bulb temperature difference = 267.9 MBh ÷ (1.085 x 12,000 cfm) = 20.6°F.
Supply air dry bulb: 81.5 - 20.6 = 60.9.
Unit enthalpy difference = 355 ÷ (4.5 x 12,000) = 6.57 Btu/lb.
Btu/lb leaving enthalpy = h (ent WB) = 31.62 Btu/lb.
From Table 8, p. 41, the leaving air wet bulb temperature corresponding to an enthalpy of
25.1 Btu/lb = 58°F.
Leaving air temperatures = 60.9°F/58°F
Heating Capacity Selection
1. Winter outdoor design conditions—0°F.
2. Total return air temperature — 72°F.
3. Winter outside air minimum ventilation load and cfm — 1,200 cfm and 87.2 MBh.
4. Peak heating load 225 MBh.
Utilizing Unit selection in the Cooling Capacity Procedure
Mixed air temperature = RADB +%O.A. (OADB - RADB) = 72 + (0.10) (0-72) = 64.8°F.
Supply air fan motor heat temperature rise = 20,600 BTU ÷ (1.085 x 12,000) cfm = 1.6°F.
Mixed air temperature entering heat module = 64.8 + 1.6 = 66.4°F.
Total winter heating load = peak heating + ventilation load - total fan motor heat = 225 + 87.2 - 22.1
= 290.1 MBh.
Electric Heating System
Unit operating on 480/60/3 power supply. From Table 22, p. 53, kw may be selected for a nominal
30-ton unit operating on 480-volt power. The high heat module — 90 KW or 307 MBh will satisfy
the winter heating load of 290.1 MBh.
Table 22, p. 53 also shows an air temperature rise of 23.6°F for 12,000 cfm through the 90 kw heat
module.
20 RT-PRC033F-EN
Selection Procedure
Unit supply temperature at design heating conditions = mixed air temperature + air temperature
rise = 66.4 + 23.6 = 90°F.
Natural Gas Heating System
Assume natural gas supply — 1000 Btu/ft3. From Table 23, p. 53 select the high heat module (486
MBh output) to satisfy 290.1 at unit cfm.
Table 23, p. 53 also shows air temperature rise of 37.3°F for 12,000 cfm through heating module.
Unit supply temperature design heating conditions = mixed air temperature + air temperature rise
= 66.4 + 37.3 = 103.7°F.
Hot Gas Reheat Dehumidification Selection
The hot gas reheat option allows for increased outdoor air ventilation. It reduces humidity levels
while increasing comfort level in the air space.
Note: Please note that hot gas reheat operation will not be allowed when there is a call for cooling
or heating.
Utilize the Trane TOPSS™selection program or contact a local Trane sales office to calculate leaving
unit air temperature, latent capacity, reheat sensible capacity, leaving unit dew point, and moisture
removal when the unit is in hot gas reheat operation.
The hot gas reheat TOPSS selection requires the following customer input values: supply fan
airflow, ambient air temperatures, entering air temperatures, and a desired reheat set point
temperature. If the conditions provided are not within the reheat operating envelope an error will
be generated in the TOPSS program. If the reheat set point is not obtainable at the provided
conditions the customer will be required to make adjustments to the conditions or change the
reheat set point value.
Air Delivery Procedure
Supply air fan bhp and rpm selection. Unit supply air fan performance shown in Table 24, p. 54
includes pressure drops for dampers and casing losses. Static pressure drops of accessory
components such as heating systems, and filters if used, must be added to external unit static
pressure for total static pressure determination.
The supply air fan motor selected in the previous cooling capacity determination example was 7.78
bhp with 676 rpm. Thus, the supply fan motor selected is 7.5 hp.
To select the drive, enter Ta b l e 2 7, p . 5 8 for a 30-ton unit. Select the appropriate drive for the
applicable rpm range. Drive selection letter C with a range of 650 rpm, is required for 676 rpm.
Where altitude is significantly above sea level, use Ta bl e 9 , p. 42 , Ta bl e 10 , p . 42 and Figure 3, p. 42
for applicable correction factors.
Unit Electrical Requirements
Selection procedures for electrical requirements for wire sizing amps, maximum fuse sizing and
dual element fuses are given in the electrical service selection of this catalog.
Unit Designation
After determining specific unit characteristics utilizing the selection procedure and additional job
information, the complete unit model number can be developed using the model number
nomenclature page.
RT-PRC033F-EN21
Selection Procedure
0510152025303540
0
10
20
30
40
50
60
70
80
90
100
110
120
B C
FAN MOTOR HEAT - MBH
MOTOR BRAKE HORSE POWER
STANDARD MOTOR
HIGH EFFICIENCY MOTOR
Figure 2. Fan motor heat
50 Hz Units
Five basic areas
1. Cooling capacity
2. Heating capacity
3. Air delivery
4. Unit electrical requirements
5. Unit designation
Cooling Capacity Selection
1. Summer design conditions – 95 DB/76 WB (35/24.4°C), 95°F (35°C) entering air to condenser.
6. Return air temperatures – 80 DB/66°F WB (26.7/18.9°C).
7. Return air cfm – 3540 cfm (1671 L/s).
8. Outside air ventilation cfm and load – 1000 cfm and 15.19 MBh (1.27 tons or 4.45 kW) 472 L/s.
9. Unit accessories include:
a. Aluminized heat exchanger – high heat module.
b. 2” Hi-efficiency throwaway filters.
c. Exhaust fan.
d. Economizer cycle.
Selection Procedure
Step 1.
A summation of the peak cooling load and the outside air ventilation load shows: 22.5 tons + 1.27
tons = 23.77 (79 kW + 4.45 kW = 83.45) required unit capacity. From Table 34, p. 64, 25.4 ton (89 kW)
unit capacity at 80 DB/67 WB (27/19°C), 95°F entering the condenser and 10,000 total peak supply
cfm (4720 L/s) is 297 MBh (24.75 tons).
Step 2.
Having selected the correct unit, the supply fan and exhaust fan motor bhp must be determined.
Supply Air Fan
Using Table 58, p. 86, determine unit static pressure at design supply cfm:
A psychrometric chart can be used to more accurately determine the mixture temperature to the
evaporator coil.
Step 4.
Determine Total Required Unit Cooling Capacity
Required capacity = total peak load + O.A. load + supply air fan motor heat. From Figure 2, p. 22,
the supply air fan motor heat for 5.11 bhp = 14 MBh. Capacity = 270 + 15 + 14 = 299 MBh (89 kW)
Step 5.
Determine Unit Capacity
From Ta bl e 3 4, p. 6 4 unit capacity at 81.5 DB/67 WB entering the evaporator, 10,000 supply air cfm,
95°F (35°C) entering the condenser about 298 MBh (87 kW) with 243 MBh (71.1 kW) sensible.
Step 6.
Determine Leaving Air Temperature
Unit sensible heat capacity, corrected for supply air fan motor heat 243 - 14 = 229 MBh (67 kW).
Supply air dry bulb temperature difference = 229 MBh ÷ (1.085 x 10,000 cfm) = 21.1°F (-6.1°C)
Supply air dry bulb: 81.5-21.1 = 60.4 (15.8°C)
Unit enthalpy difference = 298 ÷ (4.5 x 10,000) = 6.62
3. Winter outside air minimum ventilation load and cfm – 1,000 cfm and 87.2 MBh.
4. Peak heating load 150 MBh.
Utilizing unit selection in the cooling capacity procedure.
Mixed air temperature = RADB +% O.A. (OADB - RADB) = 72 + (0.10) (0-72) = 64.8°F.
Supply air fan motor heat temperature rise = 20,600 Btu ÷ (1.085 x 10,000) cfm= 1.9°F.
Mixed air temperature entering heat module = 64.8 + 1.9 = 66.7°F.
Total winter heating load = peak heating + ventilation load - total fan motor heat = 150 + 87.2 - 14
= 223.2 MBh.
Electric Heating System
Unit operating on 415 power supply. From Table 50, p. 80, kW may be selected for TC*305 unit to
satisfy the winter heating load. The 67 kW module will do the job.
Table 50, p. 80 also shows an air temperature rise of 21.2°F for 10,000 cfm through the 67 kW heat
module.
Unit supply temperature at design heating conditions = mixed air temperature + air temperature
rise = 66.7 + 21.2 = 87.9°F.
Natural Gas Heating System
Assume natural gas supply – 1000 Btu/ft3. From Table 53, p. 80, select the low heat module
(243 MBh output) to satisfy 223 at unit cfm.
Table 53, p. 80 also shows air temperature rise of 37.3°F for 10,000 cfm through heating module.
Unit supply temperature design heating conditions = mixed air temperature + air temperature rise
= 66.7 + 37.3 = 104.0°F.
Hot Gas Reheat Dehumidification Selection
The hot gas reheat option allows for increased outdoor air ventilation. It reduces humidity levels
while increasing comfort level in the air space.
Note: Please note that hot gas reheat operation will not be allowed when there is a call for cooling
or heating.
Utilize the Trane TOPSS™selection program or contact a local Trane sales office to calculate leaving
unit air temperature, latent capacity, reheat sensible capacity, leaving unit dew point, and moisture
removal when the unit is in hot gas reheat operation.
The hot gas reheat TOPSS selection requires the following customer input values: supply fan
airflow, ambient air temperatures, entering air temperatures, and a desired reheat set point
temperature. If the conditions provided are not within the reheat operating envelope an error will
be generated in the TOPSS program. If the reheat set point is not obtainable at the provided
conditions the customer will be required to make adjustments to the conditions or change the
reheat set point value.
24 RT-PRC033F-EN
Air Delivery Procedure
Supply air fan bhp and rpm selection. Unit supply air fan performance shown in Table 54, p. 81,
Table 55, p. 83, Table 56, p. 84, and Ta bl e 5 7, p . 85 includes pressure drops for dampers and casing
losses. Static pressure drops of accessory components such as heating systems, and filters if used,
must be added to external unit static pressure for total static pressure determination.
The supply air fan motor selected in the previous cooling capacity determination example was 5.11
bhp with 601 rpm. Thus, the supply fan motor selected is 7.5 hp.
To select the drive, enter Table 59, p. 87 for a 25.4 unit. Select the appropriate drive for the
applicable rpm range. Drive selection letter D with a range of 583 rpm, is required for 601 rpm.
Where altitude is significantly above sea level, use Ta bl e 9 , p. 42 , Ta bl e 10 , p . 42 and Figure 3, p. 42
for applicable correction factors.
Unit Electrical Requirements
Selection procedures for electrical requirements for wire sizing amps, maximum fuse sizing and
dual element fuses are given in the electrical service selection of this catalog.
Unit Designation
After determining specific unit characteristics utilizing the selection procedure and additional job
information, the complete unit model number can be developed using the model number
nomenclature page.
Selection Procedure
RT-PRC033F-EN25
Model Number Descriptions
YCD330BELA0A1
12345678910111213
60 Hz Description
Digit 1, 2 — Unit Function
TC = DX Cooling, No Heat
TE = DX Cooling, Electric Heat
YC = DX Cooling, Natural Gas Heat
Digit 3 — Unit Airflow Design
D = Downflow Supply and Return
H = Horizontal Supply and Return
F=Horizontal Supply and Upflow
A =550 RPMH = 500 RPM
B =600 RPM J =525 RPM
C =650 RPMK = 575 RPM
D =700 RPML =625 RPM
E= 750 RPMM = 675 RPM
F=790 RPMN = 725 RPM
G =800 RPM
Digit 15 — Fresh Air Selection
A= No Fresh Air
B =0-25% Manual Damper
C =0-100% Economizer, Dry Bulb
Control
D =0-100% Economizer,
Reference Enthalpy Control
E= 0-100% Economizer,
Differential Enthalpy Control
F=“C” Option and Low Leak
Fresh Air Damper
G =“D” Option and Low Leak
Fresh Air Damper
H =“E” Option and Low Leak
Fresh Air Damper
J=“C” Option and Ultra Low Leak
Outside Air Damper
K =“D” Option and Ultra Low Leak
Outside Air Damper
L=E Option and Ultra Low Leak
Outside Air Damper
1=Option “C” with Traq
2=Option “D” with Traq
3=Option “E” with Traq
4=Option “F” with Traq
5=Option “G” with Traq
6=Option “H” with Traq
7=Option “C” with Traq w/ Ultra
Low Leak Outside Air Damper
8=Option “D” with Traq w/ Ultra
Low Leak Outside Air Damper
9=Option “E” with Traq w/ Ultra Low
Leak Outside Air Damper
Digit 16 — System Control
1=Constant Volume w/Zone
Temperature Control
2=Constant Volume w/ Discharge Air
Control
4=VAV Supply Air Temperature
Control w/Variable Frequency
Drive w/o Bypass
5=VAV Supply Air Temperature
Control w/Variable Frequency
Drive and Bypass
6=Single Zone VAV w/VFD w/o
Bypass
7=Single Zone VAV w/VFD w/
Bypass
26 RT-PRC033F-EN
Model Number Descriptions
A =VAV Supply Air Temperature
B =VAV Supply Air Temperature
C =Single Zone VAV w/VFD w/o
D =Single Zone VAV w/VFD w/
Note: Zone sensors are not included
Control w/VFD w/o Bypass w/
Motor Shaft Grounding Ring
Control w/VFD w/Bypass w/Motor
Shaft Grounding Ring
Bypass w/ Motor Shaft Grounding
Ring
Bypass w/Motor Shaft Grounding
Ring
with option and must be ordered
as a separate accessory.
Miscellaneous Options
Digit 17
A =Service Valves
2
Digit 18
B =Through the Base Electrical
Provision
Digit 19
C =Non-Fused Disconnect Switch
w/External Handle
Digit 20
D =Factory-Powered 15A GFI
Convenience Outlet and
Non-Fused Disconnect Switch
w/External Handle
Digit 21
E= Field-Powered 15A GFI
Convenience Outlet
Digit 22
F=Trane Communication
Interface (TCI)
Digit 23
G =Ventilation Override
Digit 24
H =Hinged Service Access
Digit 25
H =Tool-less Condenser Hail Guards
J=Condenser Coil Guards
0=Standard Drain Pan
M =Stainless Steel Drain Pan
1=Standard Drain Pan w/
Condensate Overflow Switch
2=Stainless Steel Drain Pan w/
Condensate Overflow Switch
Digit 29 — Efficiency/ Condenser
Coil Options
0=Standard Efficiency Unit
J=Standard efficiency unit w/
K =High efficiency unit (eStage)
L=High efficiency unit (eStage) w/
Corrosion Protected Condenser
Coil
Corrosion Protected Condenser
Coil
Digit 30-31 — Miscellaneous
Options
P= Discharge Temperature
R =Clogged Filter Switch
Sensor
Digit 32 — Dehumidification
Option
T= Modulating Hot Gas Reheat
Digit 33 — Human Interface
5=Touchscreen Human Interface, 5"
Model Number Notes
1. All voltages are across the line
starting only.
2. Option includes Liquid, Discharge,
Suction Valves.
3. Supply air fan drives A thru G are
used with 27½-35 ton units only and
drives H thru N are used with 40 & 50
ton units only.
4. Electric Heat KW ratings are based
upon voltage ratings of 208/240/480/
600 V. For a 240 V heater derated to
208 V, the resulting kW rating
decreases from 36 kW to 27 kW, and
from 54 kW to 41 kW. Voltage
offerings are as follows (see Table 22,
p. 53 for additional information):
Electric
Heater
Rated
Tons
Voltage
27½
to 35
40
and
50
5. The service digit for each model
number contains 32 digits; all 32
digits must be referenced.
6. Ventilation override exhaust mode is
not available for the exhaust fan with
1= 7.5 Hp (5.6 kW)
2=10 Hp (7.5 kW)
3=15 Hp (10 kW)
4=20 Hp (15 kW)
Digit 14 – Supply Air Fan Drive
Selections
A =458 RPMH = 417 RPM
B =500 RPM J =437 RPM
C =541 RPMK = 479 RPM
D =583 RPML = 521 RPM
E= 625 RPMM = 562 RPM
F=658 RPMN = 604 RPM
G =664 RPM
3
Digit 15 – Fresh Air Selection
A= No Fresh Air
B =0-25% Manual Damper
C =0-100% Economizer, Dry Bulb
D =0-100% Economizer,
E= 0-100% Economizer,
F=“C” Option and Low Leak
G =“D” Option and Low Leak
H =“E” Option and Low Leak
J=“C” Option and Ultra Low Leak
K =“D” Option and Ultra Low Leak
L=E Option and Ultra Low Leak
1=Option “C” with Traq
2=Option “D” with Traq
3=Option “E” with Traq
4=Option “F” with Traq
Control
Reference Enthalpy Control
Differential Enthalpy Control
Fresh Air Damper
Fresh Air Damper
Fresh Air Damper
Outside Air Damper
Outside Air Damper
Outside Air Damper
5=Option “G” with Traq
6=Option “H” with Traq
7=Option “C” with Traq w/ Ultra
8=Option “D” with Traq w/ Ultra
9=Option “E” with Traq w/ Ultra Low
Low Leak Outside Air Damper
Low Leak Outside Air Damper
Leak Outside Air Damper
Digit 16 – System Control
1=Constant Volume w/ Zone
2=Constant Volume w/ Discharge Air
4=VAV Supply Air Temperature
5=VAV Supply Air Temperature
6=Single Zone VAV w/VFD w/o
7=Single Zone VAV w/VFD w/
A =VAV Supply Air Temperature
B =VAV Supply Air Temperature
C =Single Zone VAV w/VFD w/o
D =Single Zone VAV w/VFD w/
Note: Zone sensors are not included
Temperature Control
Control
Control w/Variable Frequency
Drive w/o Bypass
Control w/Variable Frequency
Drive and Bypass
Bypass
Bypass
Control w/VFD w/o Bypass w/
Motor Shaft Grounding Ring
Control w/VFD w/Bypass w/Motor
Shaft Grounding Ring
Bypass w/ Motor Shaft Grounding
Ring
Bypass w/Motor Shaft Grounding
Ring
with option and must be ordered
as a separate accessory.
Miscellaneous Options
Digit 17
A =Service Valves
2
Digit 18
B =Through the Base Electrical
Provision
Digit 19
C =Non-Fused Disconnect Switch
with External Handle
Digit 20
*=Unused Digit
Digit 21
*=Unused Digit
Digit 22
F=Trane Communication Interface
(TCI)
Digit 23
G =Ventilation Override
Model Number Descriptions
Digit 24
H =Hinged Service Access
Digit 25
H =Tool-less Condenser Hail Guards
J=Condenser Coil Guards
Digit 26
K =LCI (LonTalk)
B =BACnet Communications
Interface (BCI)
Digit 27
0=5kA SCCR
D =65kA SCCR Disconnect
Digit 28
0=Standard Drain Pan
M =Stainless Steel Drain Pan
1=Pre-Painted Steel Drain Pan w/
Condensate Overflow Switch
2=Stainless Steel Drain Pan w/
Condensate Overflow Switch
Digit 29 — Efficiency/ Condenser
Coil Options
0=Standard Efficiency Unit
J=Standard efficiency unit w/
Corrosion Protected Condenser
Coil
K =High efficiency unit (eStage)
L=High efficiency unit (eStage) w/
Corrosion Protected Condenser
Coil
Digit 30-31 — Miscellaneous
Options
P= Discharge Temperature Sensor
R =Clogged Filter Switch
Digit 32 — Dehumidification
Option
T= Modulating Hot Gas Reheat
Digit 33 — Human Interface
5=Touchscreen Human Interface, 5"
6. Ventilation override exhaust mode is
not available for the exhaust fan with
fresh air tracking power exhaust. VOM
is available for the exhaust fan
without fresh air tracking power
exhaust.
Model Number Notes
1. All voltages are across-the-line
starting only.
2. Option includes Liquid, Discharge,
Suction Valves.
3. Supply air fan drives A thru G are
used with 22.9-29.2 ton (82-105 kW)
units only and drives H through N are
used with 33.3 and 41.7 ton (120-148
kW) units only.
4. Electric Heat kW ratings are based
upon voltage ratings of 380/415 V.
Heaters A, B, C, D are used with 22.9-
29.2 ton (82-105 kW) units only and
heaters B, C, D, E are used with 33.3-
41.7 ton (120-148 kW) units only.
5. The service digit for each model
number contains 32 digits; all 32
digits must be referenced.