The eco2 packaged rooftop – Designed to meet the demands of the market for today and tomorrow.
Better Economy...
Reduce Energy Consumption
• High-efficiency eco2 rooftop units are optimized for
both R-22 and HFC-407C refrigerant, and are the
first environmentally responsible rooftop units that
meet the ASHRAE 90.1-2001 ef ficiency standards.
• Multiple steps of capacity-control offer superior of fdesign energy performance, while maintaining better control of occupant comfort.
• The OptiLogic
more than the proper amount of ventilation air is
utilized, avoiding the energy cost of conditioning
excess air.
TM
Control Center ensures that no
LD07431
The OptiLogicTM Control Center uses microprocessor logic to optimize operation of the eco2 rooftop unit.
Better Ecology...
Air Quality Features for the Indoor Environment
• A double-sloped stainless steel design ensures that
all condensate is voided from the drain pan. The drain
pan is also visible and accessible for the periodic inspection and cleaning required by IAQ standards.
• Double-wall construction of the roof, floor, doors,
and walls prevents insulation fiber from entering
the supply air. The inner liner also facilitates periodic cleaning of the unit to prevent harmful buildup of bacteria or contaminants.
• The OptiLogicTM Control Center uses microprocessor logic to analyze and optimize ventilation decisions.
• A true airflow-measurement station can be supplied,
to ensure the proper ventilation at all supply-air
volumes.
• An available sensor can monitor the CO2 level within
the building and adjust the ventilation rate on demand, to maintain the air quality at a healthy level.
50-95 Ton Model ............................................70
YORK INTERNATIONAL
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Page 4
Features and Benefits
QUALITY ROOFTOP UNIT DESIGNED T O TODA Y’S
STANDARDS
Ecological and Economical Design
• First packaged RTU that meets ASHRAE 90.1-2001
with both R-22 and R-407C Refrigerants.
• Cooling and Heating – Superior operating performance provides lower operating costs. Smaller steps
of cooling capacity provide tighter control of building
environment and occupant comfort while optimizing
energy efficiency .
• Indoor Air Quality (IAQ) – Outside air economizer
provides energy savings in free cooling mode, and
can provide a healthier and more comfortable building environment by introducing fresh outside air into
the building as needed. Indoor Air Quality (IAQ) requirements for building ventilation and comfort are
controlled through the microprocessor control panel.
Optional air flow measurement provides an accurate
means of tracking air quality and alerting the occupants or building owner to unhealthy situations.
• Premium Efficiency – Premium-efficiency motors
are available for optimum energy efficiency. All motors used on the eco2 packaged rooftop air conditioner meet U.S. EP ACT 1992 minimum requirements.
• VFDs Standard on V A V Units – V ariable-frequencydrives provide the HVAC designer with a high-efficiency, quiet and more reliable means of variable air
volume control from a packaged rooftop. On larger
rooftops, ASHRAE 90.1-1999 st andard specifies part
load efficiency requirements that make VFDs the
cost-effective solution for meeting the standard.
VFDs can save the owner up to 40% of the energy
costs compared to inlet guide vanes offered on competitive units by reducing the power requirement.
VFDs use fewer parts, which leads to more reliability . Also, with fewer moving parts, and the reduction
of speed in the fan, the VFD operates at significantly
quieter operation than the inlet guide vane which
restricts a high volume of airflow, which can actually
increase noise at part load conditions.
Additionally, the YORK VFD includes DC link reactors as standard that have harmonic filtration comparable to an AC line reactor. VFDs also provide the
added benefit of soft-starting the supply fan, which
helps to minimize demand charges associated with
inrush currents.
• Network Connectivity with BACnet, LON or Roof-Link Interface – Through optional communications
protocols, the eco2 rooftop unit can communicate to
any building automation system. There are four options available: BACnet Internet Protocol (Ethernet),
BACnet MSTP (RS485), LON or a generic RoofLink
BAS interface, depending on the type of building
automation system. Without network communications, the eco2 is designed to operate in stand-alone
mode, or via contact closures for basic control.
• Professional Appearance – A high quality powder
coat paint finish is applied to the galvanized steel
2
exterior of the eco
unit to protect it from aggressive
environments helping to maintain a factory-quality
appearance for years.
• FlexSys Underfloor Air System Configuration –
the eco
2
rooftop is the first packaged rooftop product
with designs specifically for use with the YORK FlexSys underfloor air system. Ask your local YORK
representative for more information.
Indoor Air Quality (IAQ)
• Double-Sloped Stainless Steel Drain Pan – This
double-sloped inclined stainless steel drain pan facilitates removal of evaporator condensate. Sloped
in two directions, this drain pan swiftly drains any
condensate from the unit. Best of all, the drain pan
is accessible for periodic cleaning required by IAQ
standards.
• Smart Ventilation – YORK maintains the leadership role in IAQ products with adaptive ventilation
control. The OptiLogic
TM
controls provide continuous
monitoring of air quality and take action by opening
the outside air dampers, bringing in the right amount
of fresh air before air impurities reach uncomfortable
or even dangerous levels.
• Air Flow Measurement – Precise measurement
of ventilation air flow is possible using an air flow
measurement station which can be installed in the
economizer section. Proper ventilation air flow is
required to ensure sufficient fresh air is in the building. A myriad of air flow measurement options are
available from minimum air flow to high-accuracy
full air flow capabilities. The complete system is designed as an integrated component of the
OptiLogicTM control system to ensure optimum system performance.
• Double Wall Construction – Rigid double-wall construction throughout provides ease of cleaning and
protects against insulation fiber entrainment in the
breathable air. Double-wall construction also helps
improve the acoustical characteristics of the air handling unit.
• Enhanced Filtration – The eco2 unit gives designers the flexibility to meet various IAQ requirements
with a full range of rigid and throwaway filter options
at various efficiency levels.
• Demand Ventilation – Control of the economizer
is available to maintain a desired ventilation level
based on a 0-10VDC input from a sensor . A factorysupplied CO2 sensor is available for installation in
the occupied space.
4
YORK INTERNATIONAL
Page 5
FORM 100.50-EG3 (802)
Reliable Cooling and Heating Technology
• Reliable, efficient, trouble-free operation is the true
measure of a packaged rooftop’s value. That’ s why
YORK eco2 Packaged Rooftop Air Conditioners use
established scroll-compressor technology to deliver
dependable, economical performance in a wide
range of applications. With the eco
2
Packaged
Rooftop, you get the latest generation of compressor enhancements added to the scroll’s inherent
strengths. The simplicity of a hermetic scroll compressor allows the use of fewer moving parts to
minimize breakdown. YORK also employs the latest sealing technology to avoid metal-to-metal contact. Axial sealing is accomplished with floating tip
seals, while radial sealing utilizes a microcushion
of oil. The result: a maintenance-free compressor
providing minimum wear and maximum runtime.
• Gas Furnace – The eco2 rooftop gas furnace is an
induced-draft gas furnace designed for high efficiency and reliability. The furnace uses an aluminized steel tubular heat exchanger and operates
at temperatures sufficient to prevent acidic exhaust
gases from condensing in the heat exchanger at
low fire rates, unlike drum and tube style furnaces
that generate condensation formation.
Gas heat units are U.L./C.U.L. listed and are tested
to ANSI standard Z21.47. Multiple modules provide redundancy not available in single power
burner applications.
Serviceability
• Filter Maintenance Alarm – An optional filter maintenance alarm indicates when a filter becomes dirty
and requires replacement or cleaning.
Install with Ease and Safety
• Factory Run-T ested – Each unit is subjected to a
series of quality assurance checks as well as an
automated quality control process before being runtested. Fans and drives are balanced at the factory
during testing. The factory run-test ensures safe,
proper operation when the unit is installed and reduces installation and commissioning time.
• Single-Point Power Connection – Single-point
power connection reduces installation time by providing a single-point for incoming power, including
the optional convenience outlet. All incoming power
is connected in one location, reducing the cost of
distributed power wiring.
• Rain Hoods Rotate Into Place – No bulky , field- in-
stalled rain hoods here. eco2 rain hoods ship rotated
inside the unit. Once on the job, the installer merely
rotates the hood upward, caulks and fastens it in place
with sheet metal screws – an easy , one-person job.
• Factory-mounted and Wired Controls – All control points within the unit are factory-installed, wired
and tested.
• Non-Fused Disconnect – An optional factory-installed non-fused disconnect switch simplifies unit
installation and serviceability by eliminating the need
for a separate disconnect switch. Check local codes
for acceptability .
• OptiLogicTM – Fully-integrated factory-packaged
controls are standard on every unit and include a
display unit with a 4x20 character LCD display.
OptiLogicTM continually monitors all control setpoints
and configurations. If a unit sensor fails, the controller indicates an alarm. If desired, YORK service
can provide remote monitoring and automatically
schedule a service technician to make the repair
and maintain your comfort.
• Access Doors – Full-sized access doors provide
easy access into the unit for routine maintenance
and inspection.
• Suction & Discharge Service Valves – Oversized
service valves to provide isolation and quick reclamation and charging of system refrigerant are available to minimize downtime and simplify the service
and repair task.
• Convenience Outlet – For maintenance tasks requiring power tools, an optional 110V GFCI power
supply can power lights, drills or any other power
hand tool needed.
YORK INTERNATIONAL
Design Flexibility
• Low Ambient Operation – Head-pressure control
is accomplished via a VFD motor controller rather
than an inefficient and noisy condenser fan damper.
By varying the speed of the condenser fan, better
control and quieter operation is obtained during the
cooler weather. Low ambient controls are available
on all systems offering higher mechanical cooling
capacity at low ambient conditions than competitive units.
• Hot Gas Bypass – Optional on constant volume units,
hot gas bypass reduces the cycling of compressors
which helps prolong the life of the equipment.
• Duct Air Openings – Horizontal connections are
available on select configurations, offering more
flexibility for duct layout and improving sound transmission characteristics.
• Compressor Sound Blankets – For applications
in sound-sensitive areas, compressor sound blankets are available to reduce sound emitted from
the rooftop unit.
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Page 6
Features and Benefits (continued)
• Fan Spring Isolators – One-inch spring isolation
is used to prevent vibration transmission from the
rooftop unit’s supply fan to the building. Two-inch
spring isolation is also available.
• Harsh Environments – A variety of coil coating and
materials are available as well as hail guards to protect coils from weather damage.
ANGLED OR
RIGID FLAT
FILTER
SECTION
OPTIONAL
AIRFLOW
MEASUREMENT
STATION
RAINHOODS TO
PREVENT
MOISTURE
FROM ENTERING
THE UNIT
FACTORYINSTALLED
OPTILOGIC
ROOFTOP
UNIT
CONTROLLER
V-BANKED
CONDENSER
COILS TO
PROTECT
FROM HAIL
DAMAGE
COMPLETE
DOUBLE-WALL
CONSTRUCTION
OF WALLS,
FLOORS,
CEILING,
AND PANELS
DOUBLE-SLOPED
STAINLESS STEEL
IAQ DRAIN
PAN AND
INTERMEDIATE
DRAIN PAN
ANGLED
EVAPORATOR
COIL FOR
LOWER
FACE
VELOCITIES
DOORS ON BOTH
SIDES OF UNIT
AND TIE BACKS
FOR UNIT
SERVICING
CENTRIFUGAL
FAN POWERED
EXHAUST
00567VIP
6
YORK INTERNATIONAL
Page 7
FORM 100.50-EG3 (802)
NOMENCLATURE
BASIC MODEL NUMBER
1 2 3 45 6 78 91011 1213 1415 16
BASE PRODUCT TYPENOMINAL CAP ACITYAPPLICATION REFRIGERANT VOLTAGEDUCT LOCA TIONSDESIGN SPECIAL
Y0 5 0B 45BA
P055CLX
: YORK
: Packaged
Rooftop
A065B
: Air-Cooled
L075CS
: Scroll
: 50-ton
: 55-ton
: 60-ton
060RS
: 65-ton
: 70-ton
070R
: 75-ton
: 80-ton
080N
: 85-ton
085G
: 90-ton
090E
: 95-ton
095C
: Cooling Only
: Natural Gas Heat
: Natural Gas Heat SS HX
: Electric Heat
: Constant Volume
V
: VAV, VFD
F
: FlexSys
: R-407C
: R-22
: 400 / 3 / 50
: Bottom Supply
: Left Supply
: Right Supply
: Bottom Return
: Front Return
: Side Return
: Rev. Level A
: Special
: Std. Product
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Page 8
Application Data
LOCATION
Of the many factors that can affect the acoustical characteristics of a rooftop installation, one of the most important is the unit location. Ideally , the rooftop unit should
be installed away from sound-sensitive areas, such as
conference rooms, auditoriums and executive offices.
Possible locations could be above storage areas, hallways, mechanical or utility rooms, or bathrooms.
The eco
door installation. When selecting a site for installation,
be guided by the following conditions:
• Unit must be installed on a level surface.
• For the outdoor location of the unit, select a place
• Also avoid locations beneath windows or between
• Optional condenser coil protection should be used
• The unit should be installed on a roof that is struc-
• Location of unit(s) should also be away from build-
• Be sure the supporting structures will not obstruct
• Proper service clearance space of 6-feet around
RIGGING
2
air conditioning units are designed for out-
having a minimum sun exposure and an adequate
supply of fresh air for the condenser.
structures.
for seashore locations or other harsh environments.
turally strong enough to support the weight of the
unit with a minimum of deflection. It is recommended that the unit(s) be installed not more than
15 feet from a main support beam to provide proper
structural support and to minimize the transmission
of sound and vibration. Ideally, the center of gravity should be located over a structural support or
building column.
ing flue stacks or exhaust ventilators to prevent possible reintroduction of contaminated air through the
outside air intakes.
the duct, gas or wiring connections.
the perimeter of the unit, 8-feet on one side for coil
servicing, and 12-feet to any adjacent units is required to eliminate cross contamination of exhaust
and outdoor air, and for maintenance tasks such
as coil pull and cleaning. No obstructions should
be above the condensing unit section.
Spreader bars must be used by cranes to prevent damage to the unit casing. All lifting lugs must be used when
lifting the rooftop unit. Fork lifts will damage the roof top
unit and are not recommended.
Care must be taken to keep the unit in the upright position during rigging and to prevent damage to the watertight seams in the unit casing. Avoid unnecessary jarring or rough handling.
Ground Level Locations
It is important that the units be installed on a substantial base that will not settle, causing strain on the refrigerant lines and sheet metal and resulting in possible
leaks. A one-piece concrete slab with footers extended
below the frost line is highly recommended. Additionally , the slab should be isolated from the main building
foundation to prevent noise and vibration transmission
to the building structure.
For ground level installations, precautions should be
taken to protect the unit from tampering by , or injury to,
unauthorized persons. Erecting a fence around the unit
is common practice.
ECONOMIZER
The economizer section is used for ventilation of the
conditioned space to maintain indoor air quality, and
also to reduce energy consumption by using outdoor
air cooling in lieu of mechanical cooling. If outdoor air
is appropriate for cooling, but not sufficient for the cooling demand, mechanical cooling will stage on as necessary until the cooling load is met.
Dual (comparative or differential) enthalpy operation is
the most accurate and efficient means of economizer
operation. The OptiLogicTM control monitors the return
and outside air energy content, and selects the lower of
the two for operation.
V AV SUPPLY AIR PRESSURE CONTROL
Traditional packaged rooftop systems use inlet guide
vanes (IGVs) for duct static pressure control. These control supply duct pressure by modulating dampers (introduc ing losses and inefficiencies) on the inlet of the fan,
open and closed. YORK’s variable frequency drives
(VFDs) offer superior fan speed control and quieter,
energy efficient operation.
Proper rigging and handling of the equipment is mandatory during unloading and setting it into position to
retain warranty status.
8
YORK INTERNATIONAL
Page 9
FORM 100.50-EG3 (802)
For V AV applications, the YORK eco2 unit uses a VFD
to modulate fan speed and maintain a constant duct
static pressure. VFDs offer superior control over the
operation of the unit at part load, and offer the additional benefits of quieter and more efficient operation
when compared to IGV.
HARSH ENVIRONMENTS – CONDENSER AND
EV APORATOR COIL PROTECTION
For harsh environmental conditions such as seashore
applications, YORK offers three types of coil protection: copper fin material, black fin and Technicoat coatings. YORK recommends that for corrosive environments that copper fins be used to protect the evaporator and/or condenser coils. In areas where chemicals
that can corrode copper are present, such as ammonia, YORK recommends that the black fin or Technicoat
coating be used for maximum protection.
Copper Fin Condenser Coil
Copper fins can be used instead of aluminum for additional corrosion protection, however it is not suitable
for areas that are subject to acid rain or exposed to
ammonia.
Pre-Coated Condenser Fins
Black fin coating (yellow fin for evaporator fins) is precoated application epoxy on aluminum fin stock to guard
from corrosive agents and insulate against galvanic potential. It is used for mild seashore or industrial locations. This can provide corrosion resistance comparable
to copper fin coils in typical seashore locations.
Post-Coated Condenser Fins
T echnicoat (a post-coated application of epoxy) can be
used for seashore and other corrosive applications with
the exception of strong alkaloides, oxidizers, wet bromide, chlorine and fluorine in concentrations greater
than 100 ppm.
Any of the above suitable options should be selected
based on the particular project design parameters and
related environmental factors. The application should
be further reviewed and approved by the consulting engineer or owner based on their knowledge of the job
site conditions.
BUILDING EXHAUST SYSTEMS
Building exhaust systems are often necessary when
economizers are used to bring in outdoor air. Without
proper building exhaust, the building may become overpressurized. The exhaust system maintains the proper
building pressure by expelling the appropriate amount
of air from the building. Exhaust systems are typically
designed to exhaust approximately 10% less air than
what is entering the building. This provides a slight positive pressure in the building.
100% modulating exhaust with building static
pressure sensing and control
The 100% exhaust system can be configured with either control actuated dampers or VFDs for modulating
control. The unit controller monitors the building pressure using a differential pressure transducer and maintains the required building static pressure by modulating the exhaust control. If the building has other means
of exhaust or building pressure is not important, on/off
or barometric control may be used.
Powered exhaust with fan on/off control
The 100% exhaust system can be configured for on/off
operation eliminating the expense of the damper actuators or VFDs. This exhaust system can be controlled
by either the outside air damper position, or a building
static pressure sensor.
Barometric exhaust
Barometric exhaust can be used when smaller amounts
of air at low static pressure variations within the building or other means of building exhaust are employed.
Barometric exhaust is commonly used where there are
only small fluctuations in building pressure or where
building static pressure control is not necessary .
ROOF CURB
YORK offers optional roof curbs designed specifically
for the eco
2
footprint. These curbs come disassembled
and require field assembly and installation. For bottom
supply and return openings, the curbs have matching
connections to ease installation. A pipe chase that
matches the rooftop unit pipe chase is also included in
the curb footprint for through-the-curb utility connections.
YORK INTERNATIONAL
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Page 10
Application Data (continued)
The curb should be located according to the location
recommendations above, and properly sealed to prevent moisture and air leakage into and out of the duct
system. Flexible collars should be used when connecting the duct work to prevent unit noise transmission
and vibration into the building.
Duct work should be supported independently of the
unit.
ACOUSTICAL CONSIDERA TIONS
The eco
competitive units by using flexible fan connections, fan
spring isolators, double-wall construction, and lower
speed and horsepower fans. For VAV applications,
VFDs are used instead of inlet guide vanes. Additional
sound attenuation can be obtained using compressor
sound blankets and field-supplied sound attenuators
when necessary.
Even with these equipment design features, the acoustical characteristics of the entire installation must never
be overlooked. Additional steps for the acoustical characteristics of a rooftop installation should be addressed
during the design phase of a project to avoid costly alterations after the installation of the equipment. During
the design phase of a project, the designing engineer
should consider, at a minimum, the imp act of the equipment location, rooftop installation, building structure, and
duct work.
2
unit is designed for lower sound levels than
Select Unit:
1. Determine the internal static pressure drop of the
cabinet by referencing Table 17.
3. Determine the BHP of the supply fan from Table 15
using the supply air flow and total static pressure.
From the table, we interpolate to get 26.3 BHP at
724 rpm.
4. Determine the motor heat gain of supply air flow by
first calculating the motor energy and converting it
into Btuh.
Motor Energy
Motor kW = BHP x .746/efficiency
Motor kW = 26.3 x 0.746/0.94
Motor kW = 20.9 kW
SELECTION PROCEDURE
Given:
Total Cooling Load920 mbh
Sensible Heat610 mbh
Required Heating Capacity875 mbh
Design Cooling Ambient Temp.95°F
Indoor Air Temperature80°F db/67°F wb
Supply Air Flow24,000 cfm
External Static Pressure2.25 in. w.c.
Electrical Service460V/3ph/60 Hz
Unit Configuration/Options: 0-100% modulating economizer, barometric relief, premium ef ficiency supply fan
motor and VFD, and two-inch pleated filters, bottom
supply, bottom return.
10
Motor Heat Rejection (MHR)
MHR = 2545 x BHP/efficiency
MHR = 2545 x 26.3/0.94
MHR = 71.2 mbh
5. Calculate actual required tot al cooling capacity by
adding specified cooling capacity to motor heat
rejection.
Required T ot al Cooling Capacity
920 mbh + 71.3 mbh = 991 mbh
Required Sensible Cooling Capacity
610 mbh + 71.3 mbh = 681 mbh
YORK INTERNATIONAL
Page 11
FORM 100.50-EG3 (802)
6. Required total and sensible capacities are 991 mbh
and 681 mbh, respectively . The total capacity is 82.6
tons, therefore a model YP AL085 is selected. Use
the Cooling Performance Data in Table 9. Locate
the table with the correct ambient air temperature.
Next, trace the 80°F entering air dry bulb temperature to match the 24,000 cfm and 67°F entering
wet bulb temperature condition. The resulting conditions are, from the table, 996.5 mbh total cooling
capacity and 688.9 mbh sensible cooling capacity .
7. The high heat option for the YPAL085 provides
900 mbh of heat capacity with an input of 1,125
mbh. This is sufficient for the 875 mbh heating
requirement.
8. Determine net cooling and heating capacities if
required.
Net Cooling Capacity (NCC)
mbh = 996.5 mbh – 71.3 mbh
mbh = 925 mbh
Net Sensible Heat Capacity (NSHC)
mbh = 688.9 mbh - 71.3 mbh
mbh = 618 mbh
Net Heating Capacity (NHC)*
mbh = 875 mbh + 71.3 mbh
mbh = 946 mbh
* Note, net heating capacity is approximate because this example
uses the bhp calculated based on a wet evaporator coil (for
cooling mode).
Quantity11111
TypeFCFCFCFCFC
Size25-2225-2225-2225-2228-25
Motor Size Range (Min. to Max. HP)7.5-407.5-407.5-407.5-407.5-60
Air Flow Range (Min. to Max. m3/hr)16,988-38,228 16,988-38,228 23785-4587523785-45875 23785-54,367
Static Pressure Range (Min. to Max. ESP)0-995 Pa0-995 Pa0-995 Pa0-995 Pa0-995 Pa
Exhaust Fan
Quantity22222
TypeFCFCFCFCFC
Size15-1515-1515-1515-1518-18
Motor Size Range (Min. to Max. HP)5-205-205-205-2010-20
Air Flow Range (Min. to Max. m3/hr)0-339800-339800-339800-339800-33980
Static Pressure Range (Min. to Max. ESP)0-498 Pa0-498 Pa0-498 Pa0-498 Pa0-498 Pa
12
YORK INTERNATIONAL
Page 13
FORM 100.50-EG3 (802)
T ABLE 1 – PHYSICAL DATA – MODELS 50-70 (CONT’D)
MODEL SIZE050055060065070
Evaporator Coil
Size (Square Meters)55555
Number of Rows/Fins per cm11111
Tube Diameter (cm) /Surface5/4 /enhanced5/4 /enhanced5/4 /enhanced5/4 /enhanced5/4 /enhanced
Condenser Coil (Aluminum Fins)
Size (Square Meters)11111111182
Number of Rows/Fins per cm11000
Tube Diameter (cm)11111
Condenser Coil (Copper Fins - Opt)
Size (square meters)1111111117
Number of rows/fins per cm11000
Tube Diameter11111
Condenser Fans
Quantity44446
TypeProp.Prop.Prop.Prop.Prop.
Diameter (Meters)11111
Power (Hp Each)22222
Filters - 5.08cm Throwaway
Quantity 8 / 12 8 / 12 8 / 12 8 / 12 10 / 15
Size (Length x Width) (Meters).6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)66667
Filters - 5.08cm Cleanable
Quantity 8 / 12 8 / 12 8 / 12 8 / 12 10 / 15
Size (Length x Width) (Meters).6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)66667
Filters - 5.08cm Pleated (30% Efficient)
Quantity8 / 12 8 / 12 8 / 12 8 / 12 10 / 15
Size (Length x Width) (Meters).6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)66667
Quantity11111
TypeFCFCFCFCFC
Size28-2528-2528-2528-2828-28
Motor Size Range (Min. to Max. Hp)7.5-607.5-607.5-607.5-607.5-60
Air Flow Range (Min. to Max. m3/hr)23785-54,367 23785-54,36730582-6116430582-61164 30582-61164
Static Pressure Range (Min. to Max. ESP)0-995 Pa0-995 Pa0-995 Pa0-995 Pa0-995 Pa
Exhaust Fan
Quantity22222
TypeFCFCFCFCFC
Size18-1818-1818-1818-1818-18
Motor Size Range (Min. to Max. HP)10-2010-2010-2010-2010-20
Air Flow Range (Min. to Max. m3/hr)0-339800-339800-339800-339800-33980
Static Pressure Range (Min. to Max. ESP)0-498 Pa0-498 Pa0-498 Pa0-498 Pa0-498 Pa
14
YORK INTERNATIONAL
Page 15
FORM 100.50-EG3 (802)
T ABLE 1 – PHYSICAL DATA – MODELS 75-95 (CONT’D)
MODEL SIZE075080085090095
Evaporator Coil
Size (Square Meters)55555
Number of Rows/Fins per cm11111
Tube Diameter (cm) /Surface5/4 /enhanced5/4 /enhanced5/4 /enhanced5/4 /enhanced5/4 /enhanced
Condenser Coil (Aluminum Fins)
Size (Square Meters)1717171717
Number of Rows/Fins per cm00000
Tube Diameter (cm)11111
Condenser Coil (Copper Fins - Opt)
Size (Square Meters)1717171717
Number of Rows/Fins per cm00000
Tube Diameter11111
Condenser Fans
Quantity66666
TypeProp.Prop.Prop.Prop.Prop.
Diameter (Meters)11111
Power (Hp Each)22222
Filters - 5.08cm Throwaway
Quantity 10 / 15 10 / 15 10 / 15 12 / 18 12 / 18
Size (Length x Width) (Meters)6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)77799
Filters - 5.08cm Cleanable
Quantity10 / 15 10 / 15 10 / 15 12 / 18 12 / 18
Size (Length x Width) (Meters).6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)77799
Filters - 5.08cm Pleated (30% Efficient)
Quantity10 / 15 10 / 15 10 / 15 12 / 18 12 / 18
Size (Length x Width) (Meters).6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)77799
Filters -30.48cm Rigid 65%, 5.08cm 30% Prefilter
Quantity2 / 8 / 92 / 8 / 92 / 8 / 9 8 / 12 8 / 12
Size (Length x Width) (Meters).4x.5 /.6x.4 /.6x.5.4x.5 /.6x.4 /.6x.5.4x.5 /.6x.4 /.6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)11122
Filters -30.48cm Rigid 95%, 5.08cm 30% Prefilter
Quantity2 / 8 / 92 / 8 / 92 / 8 / 9 8 / 12 8 / 12
Size (Length x Width) (Meters).4x.5 /.6x.4 /.6x.5.4x.5 /.6x.4 /.6x.5.4x.5 /.6x.4 /.6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)11122
Filters - 5.08cm Carbon (30% Efficient)
Quantity 10 / 15 10 / 15 10 / 15 12 / 18 12 / 18
Size (Length x Width) (Meters).6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5.6x.4 / .6x.5
Total Filter Face Area (Square Meters)22222
Minimum OA Temp. for Mech. Cig.4545454545
YORK INTERNATIONAL
15
Page 16
Cooling Performance Data – 50 Ton Model
T ABLE 2 – COOLING PERFORMANCE DA TA* – 50 TON MODEL
In order to determine the proper exhaust fan motor size,
add the return duct static pressure to the appropriate
damper pressure drop value in Table 23 to get the total
static pressure applied to the exhaust fan. Based on
the exhaust fan air flow and total static pressure, determine the brake horsepower and RPM of the exhaust
fan.
In order to use the electrical service required for the cooling only eco2 rooftop, use the appropriate calculations
listed below from U.L. 1995. Based on the configuration
of the rooftop, the calculations will yield different MCA
(minimum circuit ampacity), and MOP (maximum
overcurrent protection).
Using the following load definitions and calculations,
determine the correct electrical sizing for your unit. All
concurrent load conditions must be considered in the
calculations, and you must use the highest value for
any combination of loads.
Load Definitions:
• LOAD1 is the current of the largest motor – compressor or fan motor.
• LOAD2 is the sum of the remaining motor currents
that may run concurrently with LOAD1.
• LOAD3 is the current of the electric heaters – zero
for cooling only units.
• LOAD4 is the sum of any remaining current s greater
than or equal to 1.0 amp.
Use the following calculations to determine MCA
and MOP for units supplied with a single-point power
connection:
MCA = (1.25 x LOAD1) + LOAD2 + LOAD3 + LOAD4
MOP = (2.25 x LOAD1) + LOAD2 + LOAD3 + LOAD4
If the MOP does not equal a standard current rating of
an overcurrent protective device, then the marked maximum rating is to be the next lower standard rating. However, if the device selected for MOP is less than the
MCA, then select the lowest standard maximum fuse
size greater than or equal to the MCA.
The control system for the YORK eco² Packaged Rooftop Unit is fully self-contained and based around an
OptiLogic
maintenance, and operation, the OptiLogic™ rooftop unit
controller is equipped with a user interface that is based
around a 4 line x 20 character backlit LCD display . The
LCD displays plain language text in a menu-driven format to facilitate use. In addition to the display, the
OptiLogic™ user interface is also equipped with an LED
indicator light, which will warn of any abnormal operation of the equipment or communication failures.
For the maximum in system flexibility, the YORK eco²
Packaged Rooftop Unit can be operated by either a typical 7-wire thermostat (2 cool/2 heat), a space temperature sensor, or stand-alone (VAV only). Note, a field
wiring terminal block is provided to facilitate unit setup
and installation.
In lieu of the hard-wired control options, the OptiLogic
rooftop unit controller can be connected to and operated by a Building Automation System (BAS). If required,
the OptiLogic™ rooftop unit controller can be equipped
with an optional BACNet IP communication card, which
allows communication, via Ethernet, to a BACNet IP
based BAS.
™
rooftop unit controller. To aid in unit setup,
Note a unit operated from a space sensor can be
equipped to temporarily override an unoccupied mode
of operation. This Unoccupied Override feature is fully
configurable via the OptiLogic™ user interface.
GAS HEA TING OPERA TION
Units supplied with gas heat can be equipped one, two,
or three independently operated burner modules. Each
module is fully self-contained furnace with all necessary ignition controls, safeties, and gas valves. The
OptiLogic rooftop unit controller determines how the
furnaces are started and stopped and prevents furnace
operation if the Supply Fan airflow is not sufficient or if
the Supply Air Temperature is excessively high.
If a furnace module receives a signal to start from the
OptiLogic controller, the ignition control engages the
furnace inducer (draft) fan for a 30-second pre-purge
cycle. At the end of the 30-second pre-purge, the ignition control will stop the furnace and allows the inducer
™
fan to operate for a 30-second post-purge. Each furnace contains a direct spark ignition system and included safeties for flame and inducer fan verification,
high temperature and flame roll-out.
MORNING WARM-UP
UNOCCUPIED / OCCUPIED SWITCHING
Depending on application, the unit can be indexed between unoccupied and occupied modes of operation
by one of three methods, hard-wired input, internal time
clock, or BAS. A contact-closure input is provided for
hard-wiring to an external indexing device such as a
central time clock, thermostat with built in scheduling,
or a manual switch. The unit controller is also equipped
with a built in 7-day time clock which can be used, in
lieu of the contact closure input, to switch the unit between Unoccupied and Occupied modes of operation.
The internal time clock is fully configurable via the user
interface and includes Holiday scheduling. In addition
to the hard-wired input or the internal time clock, the
unit can also be indexed between unoccupied and occupied modes of operation via a BAS command.
Morning Warm-Up can be initialized by BAS or by the
OptiLogic controller if the Internal Scheduling is used.
If the Internal Scheduling is used, the Morning WarmUp start time is calculated through an adaptive algorithm, which determines the optimum start time.
When Morning Warm-Up is required, the OptiLogic
controller starts the Supply Fan and qualifies the Return Air Temperature for 5 minutes. The internal heat
source (Gas, HW/Steam, or Electric) is controlled to
maintain the Return Air Temperature to the Morning
Warm-Up Setpoint, Morning Warm-Up ends when occupancy occurs (BAS, Internal Scheduling, or contact
closure), or when the Maximum Morning Warm-Up
Time has expired.
54
YORK INTERNATIONAL
Page 55
FORM 100.50-EG3 (802)
ELECTRIC HEA TING OPERATION
For units equipped with electric heaters, the unit can
control up to six stages of electric heat which are staged
on based on heating demand calculates by the
OptiLogic controller.
ECONOMIZER OPERA TION
The unit can be equipped with one of three types of
optional economizers, dry bulb, single enthalpy , or comparative enthalpy . When the unit controller determines
that Outside Air is suitable for economizing, the unit
controller will control the outside air damper(s) open to
provide economizer cooling. If economizer cooling alone
is insufficient for the cooling load, the unit controller
shall stage up compressors, one at a time, to meet
demand.
The control logic for the three types of economizers is
as follows:
Dry Bulb Economizer
The dry bulb economizer is the default economizer
control scheme. With the dry bulb economizer, the
unit controller monitors the Outside Air temperature
only and compares it to a reference temperature setting. Outside Air is deemed suit able for economizing
when the Outside Air temperature is determined to
be less than the reference temperature setting. This
method of economizing is effective, but is prone to
some change-over inefficiencies due to the fact that
this method is based on sensible temperatures only
and does not take Outside Air moisture content into
consideration.
Single Enthalpy Economizer
With the optional single enthalpy economizer, the unit
controller monitors the Outside Air enthalpy in addition
to the Outside Air temperature and compares it to a
reference enthalpy setting and a reference temperature setting. Outside Air is deemed suitable for economizing when the Outside Air enthalpy is determined to
be less than the reference enthalpy setting and the
Outside Air temperature is less than the reference temperature setting. This method of economizing allows
the reference temperature setting to be set higher than
the DB Economizer and is consequently a more efficient packaged rooftop economizer .
Comparative (Dual) Enthalpy Economizer
With the optional comparative enthalpy economizer, the
unit controller monitors and compares the Outside Air
and Return Air enthalpies in addition to comp aring the
Outside Air temperature to the reference temperature
setting. Outside Air is deemed suitable for economizing when the Outside Air enthalpy is determined to be
less than the Return Air enthalpy and the Outside Air
temperature is less than the reference temperature
setting. This method of economizing is the most accurate and provides the highest degree of energy efficiency for a packaged rooftop economizer.
VENTILA TION CONTROL SEQUENCES
Minimum OA Damper Position (CV Unit s)
When the unit goes into the Occupied mode of operation, the unit controller shall open the Outside Air
Damper to a fixed minimum position. The damper shall
remain at this position as long as the unit is in the
occupied mode, and the economizer is not suitable
for cooling.
Minimum OA Damper Position (VA V Unit s)
With V ariable Air V olume units, there are two Minimum
OA Damper Positions, one when the unit is at full speed
and the second when the unit is at approximately half
speed. These two points allow the control to linearly
reset the position of the OA damper in response to fan
speed.
When the unit goes into the Occupied mode of operation, the unit controller shall monitor the speed of the
supply fan and open the Outside Air damper to a calculated minimum position based on the fan speed. This
minimum position shall vary as the speed of the fan
changes. The damper shall remain at this calculated
position as long as the unit is in the occupied mode,
and the economizer is not suitable for cooling.
Air Measurement Stations
When the unit is equipped with an air measurement
station, the unit controller shall control the Outside Air
damper to a measured flow rate through the Air Measurement St ation.
When the unit goes into the Occupied mode of operation, the unit controller shall control the Outside Air
damper to maintain the Minimum AirFlow Setpoint
YORK INTERNATIONAL
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Page 56
Controls (continued)
through the Air Measurement S tation. The unit controller shall control the Outside Air damper to this flow rate
as long as the unit is in the Occupied mode, and the
economizer is not suitable for cooling.
Demand Ventilation
If an optional CO
sensor is connected to the unit, the
2
unit controller can reset the minimum OA damper
position(s) or minimum flow rate based on demand.
The unit controller shall monitor the CO2 level within
the building. If the CO2 level rises above the CO2 setpoint,
the controller will temporarily increase the Minimum OA
Damper Position or Minimum OA flow rate to increase
ventilation. If the CO2 level drops below the CO2 setpoint,
the controller will decrease the Minimum OA Damper
Position or Minimum OA flow rate to decrease ventilation.
Demand Ventilation shall remain active as long as the
unit is in the Occupied mode of operation.
EXHAUST CONTROL SEQUENCES
Barometric
The optional barometric exhaust system consists of a
lightweight barometric relief damper installed on the end
of the unit in the Return Air section. As more outside air
is introduced into the controlled zone due to Economizer and Ventilation control sequences, the pressure
inside the building rises. This increase in building pressure forces the barometric relief damper open to allow
exhaust air to escape. Because this type of exhaust
system is not powered, it is limited to small amounts of
exhaust.
Powered Fixed Volume Exhaust Based on
Outside Air Damper Position
This optional fixed volume powered exhaust system
consists of a fixed speed fan that is controlled ON and
OFF based on the position of the Outside Air Damper.
During operation, when the Outside Air Damper opens
to a selected turn-on point, the Exhaust Fan is cycled
ON. The fan remains on as long as the Outside Air
damper is above a selected turn-off point. If the Outside Air Damper closes to the selected turn-off point,
the Exhaust Fan is cycled OFF. The turn-on and turnoff points are user selectable from the OptiLogic™ User
Interface panel.
Powered Fixed Volume Exhaust Based on
Building Pressure
The optional fixed volume powered exhaust system
consists of a fixed speed fan that is controlled ON and
OFF based on the pressure inside the building. During
operation, the pressure within the building in monitored
™
by the OptiLogic
controller. If the pressure rises to or
above a selected turn-on pressure, the Exhaust Fan is
cycled ON. The fan shall remain on as long as the pressure within the building remains above a selected turnoff pressure. If the building pressure falls to or below
the selected turn-off pressure, the Exhaust Fan is cycled
OFF. The turn-on and turn-off pressure setpoints are
user selectable from the OptiLogic
This optional variable volume powered exhaust system
consists of a fixed speed fan configured with a proportionally controlled discharge damper. The OptiLogic
controller monitors the pressure inside the building and
controls the Exhaust Damper and the Exhaust Fan. If
the Building Pressure rises, the Exhaust Damper is proportionally controlled open and the Exhaust Fan is controlled ON. If the Building Pressure falls, the Exhaust
Damper is proportionally controlled closed and the Exhaust Fan is controlled OFF. The position of the Exhaust Damper in which the Exhaust Fan is controlled
ON and OFF as well as the Building Pressure setpoint
is user selectable from the OptiLogic™ User Interface.
Powered Variable Volume Exhaust-VFD Controlled
This optional variable volume powered exhaust system
consist of an Exhaust Fan driven by a Variable Frequency Drive (VFD), which is controlled by the
OptiLogic™ controller. The OptiLogic™ controller monitors the pressure within the building. As the pressure
rises, the VFD is controlled to increase Exhaust Fan
speed. As the pressure falls, the VFD is controlled to
decrease Exhaust Fan speed. The Building Pressure
Setpoint is user selectable from the OptiLogic™ User
Interface. On/Off control is maintained the same as
Exhaust-Discharge Damper control stated above.
LOW AMBIENT OPERATION
The OptiLogic™ controller continuously monitors the
outside air temperature to determine if mechanical cooling should be allowed. As a safety, if the Outside Air
temperature falls to or below the Low Ambient Lockout
temperature, mechanical cooling is prevented from
operating. For units with economizers, the Low Ambient Lockout temperature is typically low enough that
mechanical cooling will rarely be required. However,
for some applications mechanical cooling is required
when the Outside Air temperature is lower than the Low
Ambient Lockout temperature.
™
56
YORK INTERNATIONAL
Page 57
FORM 100.50-EG3 (802)
For these applications, the unit must be equipped with
optional Low Ambient controls. For optional Low Ambient operation, the OptiLogic™ controller monitors the
refrigeration system discharge pressure and controls
the speed of the condenser fans. If the discharge pressure falls, the speeds of the condenser fans are reduced to maintain acceptable condensing pressures in
the refrigeration system. With the optional Low Ambient controls, mechanical cooling is allowed down to
Outside Air temperatures of -17.7°C.
SMOKE PURGE SEQUENCES
General
As a convenience, for when buildings catch fire or the
building is inundated with smoke or fumes from manufacturing processes, etc., the OptiLogic
™
control system provides one of five ventilation override control
sequences for building purge. The five selectable purge
sequences are, Shutdown, Pressurization, Exhaust,
Purge and Purge with duct pressure control. Note, when
any of the purge sequences are activated, cooling and
heating modes are disabled. A contact closure input is
provided which indexes the OptiLogic™ controller into
the selected purge sequence.
Shutdown
When this purge sequence is selected and activated,
the supply and exhaust fans are controlled OFF and
the Outside Air damper is overridden closed. This idle
state is maintained until the purge input is deactivated
and the unit returns to normal operation.
Pressurization
When this purge sequence is selected and activated,
the exhaust fan is controlled OFF and the Supply Fan
is controlled ON. The Outside Air damper is opened full
and the Return Air Damper is closed full. If the unit is a
VAV unit, the VAV boxes are also driven full open to
prevent duct over-pressurization. This mode is maintained until the smoke purge input is deactivated and
the unit returns to normal operation.
Purge
When this purge sequence is selected and activated,
the Supply Fan is controlled ON and the Exhaust Fan
is controlled ON. The Outside Air damper is opened full
and the Return Air damper is closed full. If the unit is a
VAV unit, the VAV boxes are also driven full open to
prevent duct over-pressurization. This mode is maintained until the smoke purge input is deactivated and
the unit returns to normal operation.
Purge With Duct Pressure Control (VAV Only)
When this purge sequence is selected and activated,
the Supply Fan is cycled ON and controlled to maintain
the duct static pressure setpoint. The Exhaust Fan is
also controlled ON (Exhaust Damper driven full open)
and the Outside Air Damper is driven full open. This
mode is maintained until the smoke purge input is deactivated and the unit returns to normal operation.
VAV SPECIFIC SEQUENCES
SUPPL Y F AN OPERATION
For V A V units, the supply fan is controlled ON and OFF
based on the occupancy state or the G input from a
Thermostat (Unit must be configured for Thermostat
operation to respond to the G input). When the unit
goes into the Occupied mode of operation (or “G” is
called) the Supply Fan will be controlled ON. The
OptiLogic™ controller will monitor the static pressure
within the supply duct system and control the speed of
the supply fan to maintain a specified Duct St atic Pressure setpoint. A V ariable Frequency Drive (VFD) is used
on all VAV units to vary the speed of the supply fan.
Note, the use of a VFD in lieu of inlet guide vanes provides for higher energy efficiency for the unit by eliminating the losses (air pressure drop) typical of inlet guide
vane systems.
COOLING OPERA TION
Thermostat Control
Exhaust
When this purge sequence is selected and activated,
the Supply Fan is controlled OFF and the Exhaust Fan
is controlled ON (Exhaust Damper driven full open and
the outside air damper is closed). This mode is maintained until the smoke purge input is deactivated and
the unit returns to normal operation.
YORK INTERNATIONAL
When a VAV unit is configured for thermostat operation, the OptiLogic™ controller will command the Supply Fan to start when the unit goes into the Occupied
mode or a thermostat “G” signal is received by the control. With no thermostat calls for cooling, the unit shall
remain idle with the Supply Fan operating as required.
When a Cooling Stage 1 call (“Y1”) is received, and the
unit is equipped with an economizer, the OptiLogic
controller will check the Outside Air conditions to deter-
57
™
Page 58
Controls (continued)
mine if conditions are suitable for economizing and
modulate the outside air damper and/or stage up compressors as required to maintain the VAV High Supply
Air Temperature Setpoint. This setpoint is user selectable at the OptiLogic
™
User Interface. The OptiLogic
controller will control to this setpoint as long as Cooling
St age 1 (“Y1”) remains active.
When a Cooling Stage 2 call (“Y2”) is received, and the
unit is equipped with an economizer, the OptiLogic
controller will check the Outside Air conditions to determine if conditions are suitable for economizing and
modulate the outside air damper and/or stage up compressors as required to maintain the VAV Low Supply
Air Temperature Setpoint. This setpoint is user selectable at the OptiLogic™ User Interface. The OptiLogic
controller will control to this setpoint as long as Cooling
St age 2 (“Y2”) remains active.
The V AV High SAT Setpoint is always greater than the
V AV Low SAT Setpoint and because of this essentially
makes this control sequence a Supply Air T emperature
Reset algorithm based on Zone Temperature or Outside Air.
Zone Sensor Control
When a V A V unit is configured for Zone Sensor operation, the OptiLogic™ controller will monitor a reference
Zone Temperature and command the Supply Fan to
start when the unit goes into the Occupied mode.
If the zone temperature is above the VAV Setpoint for
SA T Reset, the OptiLogic™ controller will modulate the
outside air damper (Economizer available and conditions suitable) and/or stage compressors up and down,
as required, to maintain the V AV High Supply Air Temperature Setpoint.
™
In Stand-Alone Mode, the OptiLogic
Controller will
monitor only the Occupied/Unoccupied state. When the
unit is commanded into the Occupied Mode of operation, the OptiLogic™ Controller will start the Supply Fan.
™
If the unit is equipped with an Economizer, the Controller will check to see if Outside Air conditions are
suitable for Economizing. The controller will then use
Outside Air (when available and suit able) and/or stage
compressors up and down, as required, to maintain
™
the V AV Low SAT Setpoint.
Supply Air Tempering
Supply Air Tempering is a continuation of the a VAV
cooling operation when the outside air temperature is
™
below the supply air temperature setpoint where heating is used to maintain economizer operation. This function will use small increments of heat to maintain the
Supply Air Temperature when the economizer damper
is at minimum position. If the unit is equipped with
stepped heat (electric or gas), the heat will be duty
cycled. A maximum of six cycles per hour is permitted
for the heating stages.
HEA TING OPERA TION
V AV Occupied Heating
When VAV Occupied Heating is enabled, full heating
will energize when either the thermostat W1 or W2 signal is received or the space temperature falls below
the V AV Setpoint for SA T Reset by more than -16.6°C.
If the return air temperature falls below the return air
temperature setpoint for occupied heating, full heat capacity will be energized.
CV SPECIFIC SEQUENCES
If the zone temperature is below or falls below the VAV
Setpoint for SAT Reset, the OptiLogic™ controller will
modulate the Outside Air Damper (Economizer available and conditions suitable) and/or stage compressors up and down, as required, to maintain the VAV
High Supply Air Temperature Setpoint.
As with thermostat operation, this sequence is also a
Supply Air T emperature Reset algorithm based on Zone
Temperature.
Stand-Alone Control
If the unit is not configured for Thermostat or Zone Sensor operation, the unit will operate in Stand-Alone Mode.
58
COOLING OPERA TION
Thermostat Control
If a 7-wire thermostat (2 Cool/2 Heat) controls the unit,
all zone temperature setpoint control is maintained at
the thermostat. With this operation, the unit remains
idle until it receives a stage call from the thermostat. If
“G” is called from the thermostat, the Supply Fan will
start. V entilation functions (if equipped) will be permitted to run with an occupied signal. Economizer functions will operate with a “G” call and a call for cooling.
YORK INTERNATIONAL
Page 59
FORM 100.50-EG3 (802)
Stage 1 (“Y1”) Call
If Y1 is called and the unit is equipped with an economizer ,
the control will check to see if the Outside Air is suitable for
economizing. If conditions are suitable for economizing, the
control will control the economizer and stage up compressors, as required, to maintain the economizer first-stage
setpoint. If conditions are not suitable for economizing or
not equipped with an economizer, the control will st age up
50% of the compressors. This shall be maintained until
Stage 1 is deactivated or S t age 2 is called.
Stage 2 (“Y2”) Call
If Y2 is called and the unit is equipped with an economizer, the control will check to see if the Outside Air is
suitable for economizing. If conditions are suitable for
economizing, the control will control the economizer and
stage up compressors, as required, to maintain the economizer second-stage setpoint. If conditions are not suitable for economizing or not equipped with an economizer,
the control will stage up 100% of the compressors. This
shall be maintained until St age 2 is deactivated.
Zone Sensor Control
If a zone sensor controls the unit, the OptiLogic
™
controller shall maintain the zone temperature setpoint.
This setpoint is user selectable at the OptiLogic™ User
Interface.
HEATING OPERATION
Thermostat Control
If a 7-wire thermostat (2 Cool/2 Heat) controls the unit,
all zone temperature setpoint control is maintained at
the thermostat. With this operation, the unit remains
idle until it receives a stage call from the thermostat. If
“G” is called from the thermostat, the Supply Fan will
start. Ventilation functions (if equipped) will be permitted to run with an occupied signal.
Stage 1 (“W1”) Call
If W1 is called and the unit is equipped with an economizer, the economizer will go to minimum position with
an occupied signal or close with an unoccupied signal.
and the control will stage up 50% of the heating steps.
This shall remain active until Stage 1 call is deactivated
or a Stage 2 call is activated.
Stage 2 (“W2”) Call
If W2 is called and the unit is equipped with an economizer, the economizer will go to minimum position with
an occupied signal or close with an unoccupied signal,
and the control will stage up 100% of the heating steps.
This shall remain active until Stage 2 call is deactivated.
Zone Sensor Control
When a zone sensor is used for control, the OptiLogic
unit controller will monitor the temperature within the
space and control the unit accordingly. A closed-loop
staging algorithm is used to stage compressors up and
down as required to maintain the desired zone temperature setpoint. If the unit is equipped with an economizer, Outside Air conditions are continuously monitored
by the control to determine if conditions are suitable for
economizing. If conditions are suitable for economizing, the OptiLogic™ controller will modulate the Outside
Air damper in addition to staging compressors up and
down to maintain the zone temperature setpoint.
™
If a zone sensor controls the unit, the OptiLogic™ controller shall maintain all zone temperature setpoints.
These setpoints are user selectable at the OptiLogic
™
User Interface.
When a zone sensor is used for control, the OptiLogic
™
unit controller will monitor the temperature within the
space and control the unit accordingly. A closed-loop
staging algorithm is used to stage heating steps up and
down as required to maintain the desired zone temperature setpoint. If the unit is equipped with an economizer, Outside Air conditions are continuously monitored
by the control to determine if conditions are suitable for
economizing. If conditions are suitable for economizing, the OptiLogic™ controller will modulate the Outside
Air damper in addition to staging heating steps up and
down to maintain the zone temperature setpoint.
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Power Wiring
e
y
G
d
3
2
1
ck
e
3
x
SINGLE-POINT POWER SUPPLY WIRING
Electrical / Controls Bo
ower Sid
ontrol Sid
ND
L
Wiring Terminal
Blo
LD06414
Line
Field Power
uppl
NOTES:
1. All field wiring must be provided through a field-supplied fused disconnect switch to the unit terminals (or optional molded
disconnect switch).
2. All electrical wiring must be made in accordance with all N.E.C. and/or local code requirements.
3. Minimum Circuit Ampacity (MCA) is based on U.L. Standard 1995, Section 36.14 (N.E.C. Section 440.34).
4. Maximum Dual Element Fuse size is based on U.L. Standard 1995, Section 36.15 (N.E.C. Section 440.22)
5. Use copper conductors only.
6. On units with an optional disconnect switch, the supplied disconnect switch is a “Disconnecting Means” as defined in the N.E.C. Section
100, and is intended for isolating the unit from the available power supply to perform maintenance and troubleshooting. This disconnect
switch is not intended to be a Load Break Device.
FIG. 1 – SINGLE-POINT POWER SUPPLY WIRING
Line
Line
Earth
roun
60
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SINGLE-POINT POWER SUPPLY WIRING
e
y
G
d
3
2
1
ck
e
3
x
ded
sc
ect
S
h
WITH NON-FUSED DISCONNECT
Electrical / Controls Bo
FORM 100.50-EG3 (802)
Power Sid
Mol
Case
Di
onn
witc
ontrol Sid
ND
L
Wiring Terminal
Blo
LD06415
Line
Field Power
Suppl
NOTES:
1. All field wiring must be provided through a field-supplied fused disconnect switch to the unit terminals (or optional molded
disconnect switch).
2. All electrical wiring must be made in accordance with all N.E.C. and/or local code requirements.
3. Minimum Circuit Ampacity (MCA) is based on U.L. Standard 1995, Section 36.14 (N.E.C. Section 440.34).
4. Maximum Dual Element Fuse size is based on U.L. Standard 1995, Section 36.15 (N.E.C. Section 440.22)
5. Use copper conductors only.
6. On units with an optional disconnect switch, the supplied disconnect switch is a “Disconnecting Means” as defined in the N.E.C. Section
100, and is intended for isolating the unit from the available power supply to perform maintenance and troubleshooting. This disconnect
switch is not intended to be a Load Break Device.
Line
Line
Earth
roun
FIG. 2 – SINGLE-POINT POWER SUPPLY WIRING WITH NON-FUSED DISCONNECT
YORK INTERNATIONAL
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2
y
G
d
G
d
3
2
1
e
ck
3
2
1
e
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3
x
Power Wiring (continued)
DUAL-POINT POWER SUPPLY WIRING
Electrical / Controls Bo
Field Power
Supply #
Field Power
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Wiring Terminal
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LD06416
NOTES:
1. All field wiring must be provided through a field-supplied fused disconnect switch to the unit terminals (or optional molded
disconnect switch).
2. All electrical wiring must be made in accordance with all N.E.C. and/or local code requirements.
3. Minimum Circuit Ampacity (MCA) is based on U.L. Standard 1995, Section 36.14 (N.E.C. Section 440.34).
4. Maximum Dual Element Fuse size is based on U.L. Standard 1995, Section 36.15 (N.E.C. Section 440.22)
5. Use copper conductors only.
6. On units with an optional disconnect switch, the supplied disconnect switch is a “Disconnecting Means” as defined in the N.E.C. Section
100, and is intended for isolating the unit from the available power supply to perform maintenance and troubleshooting. This disconnect
switch is not intended to be a Load Break Device.
FIG. 3 – DUAL-POINT POWER SUPPLY WIRING
62
YORK INTERNATIONAL
Page 63
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Field Control Wiring
Wiring Notes
1. Wiring shown indicates typical wiring.
2. All wiring is Class 2, low voltage
3. Maximum power available from the 24 VAC
terminal is 40VA
Units shall be designed for outdoor rooftop installation
on a roof curb (optional). Units shall be capable of providing mechanical cooling down to 7.2°C (-17.7°C with
a low ambient kit). Unit shall be capable of starting and
running at 48.8°C. Unit electric and gas connections
shall be either through the curb or the side of the unit.
QUALITY ASSURANCE
Units shall be rated according to ARI 360 and conform
to ASHRAE 90.1 energy ef ficiency requirements. Units
shall be shipped in a single package, fully charged with
HFC-407C (HCFC-22 optional) refrigerant. The manufacturing facility shall be registered under ISO 9001
Quality Standards for Manufacturing. All units shall be
completely factory wired and assembled, and undergo
a complete and automated factory run test. The factory
run test shall confirm proper operation of all functional
components on the unit, configure the unit controller
per the project and test the unit controller. Units shall
be E.T.L. listed and be tested according to U.L. 1995.
Casing
The unit cabinet shall be one-inch double-wall construction of all panels, doors, floor, roof and walls to provide
both maximum resistance to bacterial growth in the air
stream and superior structural integrity. All sheet metal
shall be G90 mill galvanized sheet metal, formed and
reinforced to provide a rigid assembly . Cabinet shall be
coated with baked on powder paint which, when subject to ASTM B117, 500 hour, 5% salt spray test. The
unit shall be insulated with 1-1/2 pound fiberglass insulation between the two sheet metal skins. Insulation shall
meet NFPA-90A regulations for smoke and flame
spread ratings. Single-wall units, or foil-faced insulation in the air stream shall be not acceptable.
The cabinet corner post and the intermediate side supports shall be a minimum of 16-gauge steel. All access
doors shall be a minimum of 18-gauge on the exterior
surfaces, and 20-gauge on the interior. Interior floor
panels shall be 18-gauge. All serviceable sections shall
have hinged access doors with latches on both sides
of the unit. Each door shall seal against gaskets to prevent air and water leakage.
Warranty
Manufacturer shall Warrant all equipment and material
of its manufacture against defects in workmanship and
material for a period of one year from date of initial
start-up or eighteen (18) months from date of shipment,
whichever occurs first.
SHIPPING PREP ARATION AND UNIT CLEANLINESS
All units shall be shipped from the factory shrink-wrap
in plastic to maintain a clean unit interior for maximum
indoor air quality and to protect the exterior finish of the
unit during transit. Tags and decals to aid in the service
or indicate caution areas shall be provided. Installation,
operation and maintenance manuals shall be supplied
with each unit.
CONSTRUCTION
Base
The base rail shall be constructed of 12-gauge galvanized steel, extending the full perimeter of the unit. All
components shall be supported from the base, and the
base shall include integral lifting lugs. The unit base
rail shall overhang the roof curb for water runoff and
shall have a fabricated recess with a continuous flat
surface to seat on the roof curb gasket, providing a
positive, weather tight seal between the unit and the
curb.
YORK INTERNATIONAL
The roof shall be double wall, with 18-gauge on the
external surface and 24-gauge on the interior. The roof
shall be formed with a 45 degree “drip lip” overhanging
the side walls to prevent precipitation drainage from
streaming down the side of the unit. Roof sections shall
be connected together via integral channels fastened
with screws and sealed with gasketing. Each fastened
seam shall be further protected by a sheet metal channel covering the full length of the gasket surface, making a completely water tight seal.
SUPPL Y AIR FAN
Fan shall be centrifugal type, statically and dynamically
balanced in the factory. Fan wheels shall be designed
for continuous operation at the maximum rate of fan
speed and motor HP. Fans shall be double-width,
double-inlet with forward curved blades.
The fan and motor assembly shall be mounted on a
common base to allow consistent belt tension with no
relative motion between the fan and motor shafts. The
entire assembly shall be isolated from the unit base
with 1" deflection springs. The fan discharge shall be
connected to the cabinet through a reinforced neoprene
flexible connection to eliminate vibration transmission
from the fan to the unit casing.
Bearings shall be self-aligning pillow-block re-greasable
ball bearings with an average life expectancy L50 of
200,000 hours. Grease fittings shall be accessible
through access doors.
71
Page 72
Guide Specifications (continued)
Fan motors shall be NEMA designed, Standard efficiency ball bearing type with electrical characteristics
and horsepower as specified. Motors shall be 1750
RPM, open drip proof type. The motor shall be located
within the unit on an adjustable, heavy steel base.
All fan motor drives shall be selected for a minimum
service factor of 1.2 and have fixed pitched sheaves.
AIR FILTERING SYSTEM
All filter holding frames shall be of heavy-duty construction designed for industrial applications. All filters shall
be accessible from either side via access doors on both
sides of the filter section.
All filter media shall be Class II listed under U.L. Standard 900. Filter efficiencies shall be rated in accordance
with ASHRAE Standard 52.
Two-inch throwaway filters in an angled filter rack shall
be standard. On units with rigid filters, two-inch prefilters
shall be installed upstream of the rigid filters.
AIR INLET SYSTEM
A factory installed outside air rain hood permanently
attached to the cabinet to prevent windblown precipitation from entering the unit shall cover inlet openings.
The rain hoods on the sides of the unit shall be rotated
into the cabinet and secured for shipment so that upon
installation they need only be rotated upwards and
screwed into place. The outside air hood shall contain
a removable and cleanable filter.
All damper assemblies shall be of low leak design.
Damper blades shall be fabricated from a minimum of
16-gauge galvanized steel.
A st ainless steel double-sloped drain pan shall be provided under the entire width of the evaporator coil, including all return bends. The main drain pan shall be
sloped a total of 1/4" per foot towards the drainage point
according to ASHRAE 62 guidelines. Main drain pan
shall be accessible and cleanable in the field. The condensate drain opening shall be flush with the bottom of
the drain pan to allow complete drainage.
Compressors
Compressors shall be hermetic, scroll-type, including
tip seals to provide efficient axial sealing while preventing scroll tip to base contact, controlled orbit design for
radial sealing to incorporate minimum flank-to-flank
contact for long service life, refrigerant cooled motors,
large suction side free volume and oil sump to provide
liquid handling capability , annular discharge check valve
and reverse vent assembly to provide low pressure
drop, silent shutdown and reverse rotation protection,
initial oil charge, oil level sight glass, vibration isolator
mounts for compressors, and brazed-type connections
for fully hermetic refrigerant circuits.
Condenser Coils
Condenser coils shall have 3/8" seamless copper tubes,
arranged in staggered rows, mechanically expanded into
aluminum fins. Coils shall be protected from hail damage with a “V” configuration, with individual flat coils rotated from the vertical plane for each condensing circuit.
Condenser Fans and Motors
Condenser fans shall be direct drive, propeller type,
discharging vertically. Condenser fan motors shall be
3-phase, totally enclosed air over (TEAO). Thermal
overload protection shall be provided for each condenser fan motor.
Refrigerant Piping
REFRIGERATION SYSTEM
Units shall have four compressors (six for YPAL070 -
095) for maximum load-matching capability . Each refrigerant circuit shall be controlled by two thermal expansion valves for maximum control at low load conditions.
Evaporator Coils
Evaporator coils shall be direct expansion. Coil tubes
shall be 1/2" OD copper, with internally enhanced tubes.
Fins shall be enhanced aluminum mechanically expanded to bond with the copper tubes. Coil casing shall
be fabricated from heavy gauge galvanized steel.
72
All interconnecting piping between refrigeration components shall be copper tubing with brazed joints.
Each refrigerant circuit shall be equipped with liquid line
filter drier, and moisture indicating sight glass. Each
circuit shall also have both high and low pressure
switches and include access fittings for replacement of
the pressure switches without removing charge.
Polyurethane sleeves shall protect all small diameter
distributor tubing to the evaporator coil to prevent the
tubes from copper-to-copper contact during shipment
or operation.
YORK INTERNATIONAL
Page 73
FORM 100.50-EG3 (802)
POWER SUPPLY
Unit power supply shall be 460V 3-phase 60 Hz (208,
230 and 575V optional) single-point power connections
with terminal block connections.
GAS-FIRED HEA TING SECTION
One or two (or three for the YPAL070-095) gas-fired
heating modules shall be installed to provide the heating requirements per the schedule shown on the plans.
The heat exchanger shall be of tubular design. Tubes
shall be 2-1/4" OD and constructed of minimum 20gauge, G160 aluminized steel (1.6 mil aluminum silicone alloy) for corrosion resistance.
Each gas-fired heat module shall have an induced draft
combustion fan with reliable spark ignition and redundant gas valves with pressure regulator.
An induced draft fan shall be provided to maintain a
positive flow of air through each tube, to expel the flue
gas and to maintain a negative pressure within the heat
exchanger relative to the conditioned space. Induced
draft fans shall be direct-drive.
Dual (2) high limit controllers per heating module, with
automatic reset to prevent the heat exchanger from
operating at an excessive temperature will be installed.
A safety pressure switch in the induced draf t fan motor
circuit must be provided to prevent ignition until sufficient air flow is established through the heat exchanger .
Airflow safety shall be provided by rollout switch protection and shall discontinue furnace operation if the
flue becomes restricted.
Units shall ship with an external flue to be shipped in
the unit and mounted on the job site. The flue shall
discharge products of combustion above the unit, preventing recycling of corrosive combustion gases back
through the heat exchanger. Gas heating sections shall
be U.L./CSA certified to both US and Canadian safety
standards.
ELECTRIC HEAT SECTION
An electric slip-in heater shall be installed within the
rooftop unit to provide the heating requirements per the
schedule shown on the plans. The electric heater shall
be wired in such a manner as to provide multiple steps
of capacity .
The heater shall be an industrial grade design using an
open coil(s) made of the highest grade resistance wire
containing 80% nickel and 20% chromium. The resistance coil(s) shall be adequately supported in the air
stream using ceramic bushings in the supporting framework. Terminals of the coil(s) shall be stainless steel
with high temperature ceramic bushings.
The primary high temperature protection shall be an
automatic reset type thermal cut out. Secondary protection shall be an automatic reset type thermal cut out.
Secondary protection shall be a replaceable thermal
link.
The operation of the electric heater shall be an integral
part of the roof top control system. Power connection
to the strip heater shall be through the single power
point connection for the entire unit. Electric heat shall
be E.T.L. certified.
CONTROLS
A factory-mounted unit controller with a 4x20 character
alphanumeric display and one-touch keypad shall be
included as standard. The controller and keypad shall
be housed inside the low-voltage compartment of the
control/power panel. On units with supply or exhaust
VFDs, the VFD keypads shall be located inside the
same panel as the unit controller and interface keypad.
Control operating data, setpoints, unit setup, configuration, service and history shall all be accessible via a
single key. A system alarm LED shall indicate failures
to the operator with more detail provide in the menu
screens. The user interface shall function with a simple
menu-driven display for easy access to unit data with
integral time clock for weekly and holiday scheduling.
The unit keypad shall include password protection to
prevent unauthorized access and tampering with unit
setpoints and configuration.
A single terminal strip shall be provided for all thermostat and customer hard-wire connections.
Unit controls shall be completely factory packaged and
compatible with a room thermostat. Constant volume
units shall operate with a two (2) cool/two (2) heat thermostat. St aging decisions shall be based upon the deviation of space temperature from set point and the rate
of change of the space temperature.
VAV units shall operate with a sensor in the supply air
stream for cooling operation. Staging decisions shall
be based upon the deviation of supply air temperature
from set point and the rate of change of the supply air
temperature.
Controllers shall have the following safeties (both VAV
and CV):
YORK INTERNATIONAL
73
Page 74
Guide Specifications (continued)
• High and low pressure cutouts (one each refrigerant circuit)
• Minimum on time for compressors
• Delay between compressor stages
• Anti-short cycle delays (minimum off time) for compressors and supply fan
• Cooling lockout at 7.2°C; -17.7°C if equipped for
low ambient operation
• Air flow proving switch which proves that the fan is
operational
POWER OPTIONS
Single-Point Supply with Terminal Block – includes
enclosure, terminal-block, and interconnecting wiring to
the compressors. Separate external protection must be
supplied, by others, in the incoming compressor power
wiring. (Do not include this option if either the Single-Point
Non-Fused Disconnect Switch or Single-Point Circuit
Breaker options have been included.)
Single-Point Supply with Non-fused Disconnect
Switch – A unit-mounted disconnect switch with exter-
nal, lockable handle (in compliance with Article 440-14
of N.E.C.), can be supplied to isolate the unit power voltage for servicing. Separate external fusing must be supplied, by others in the power wiring, which must comply
with the National Electric Code and/or local codes. (This
option includes the Single-Point Power connection.)
Dual-Point Supply with Terminal Block – includes
enclosure, one terminal-block with interconnecting wiring to the supply and exhaust fans and control transformer and a second terminal block with interconnecting wiring to the compressors and condenser. Separate external protection must be supplied, by others, in
the incoming compressor power wiring.
Convenience Outlet – an optional 1 15V convenience
outlet can be provided to power hand tools for servicing the rooftop unit.
CONTROL OPTIONS
Note: On standard units, mechanical cooling may op-
erate down to 7.2°C.
Low Ambient on Systems One and T wo – This option
includes low ambient control of the first and second refrigerant system down to -17.7°C through the use of discharge pressure transducers and variable speed drives
that will vary the speed of the condenser fans to control
condensing pressure. This option applies to YPAL050065 models. On YP AL070-095 models, mechanical cooling with system three is locked out below 7.2°C.
Low Ambient on Systems One, Two and Three –
This option includes low ambient control of the first,
second, and third refrigerant system down to -17.7°C
through the use of discharge pressure transducers and
variable speed drives that will vary the speed of the
condenser fans to control condensing pressure. This
option not available on models YP AL050-065.
Low Ambient on System One + Transducers on
System 2 (and 3 for YPAL070-095) – on standard
units, mechanical cooling may operate down to 7.2°C.
This option includes low ambient control of the first
refrigerant system down to -17.7°C through the use of
suction and discharge pressure transducers on system one. Suction and discharge pressure transducers are included on remaining system(s) for readout
only. Mechanical cooling with remaining system(s) is
locked out below 7.2°C.
Pressure Transducer with Readout Cap ability – suction and discharge pressure transducers are configured
for pressure readout of all systems. This option is available only on units without low ambient control. Low ambient options already include pressure transducers on
those specific systems. The two options listed directly
before this option describe option combinations of low
ambient and pressure transducer readout options.
Wall-Mount Zone Sensor , No Setpoint Adjustment –
a 1 kOhm thin-film nickel zone sensor for wall mounting.
This zone sensor is for sensing temperature only, and
does not include any setpoint adjustment features.
Wall-Mount Zone Sensor, Scaled Setpoint Adjustment – a 1 kOhm thin-film nickel zone sensor for wall
mounting. This zone sensor is for sensing temperature and includes a scaled temperature setpoint adjustment feature.
Low Ambient on System One – This option includes
low ambient control of the first refrigerant system down
to 0°F through the use of discharge pressure transducer and a variable speed drive that will vary the speed
of the condenser fan to control condensing pressure.
Mechanical cooling with system two (and three for
YP AL070-095) is locked out below 7.2°C.
74
Wall-Mount Zone Sensor, Nonscaled Setpoint Adjustment – a 1 kOhm thin-film nickel zone sensor for
wall mounting. This zone sensor is for sensing temperature and includes a non-scaled (warmer-cooler) setpoint adjustment feature.
YORK INTERNATIONAL
Page 75
FORM 100.50-EG3 (802)
BACNet IP Communications Card – for BAS communications, a BACNet card is available for ethernet
connection.
BACNet MSTP Communications Card – for BAS communications, a BACNet MSTP card is available for an
RS-485 connection.
bon or pleated filters in an angled rack are available.
Additionally, twelve-inch 65% or 95% efficient rigid filters in a flat rack with two-inch prefilters. For
field-supplied filters, the unit may be ordered with a rigid
filter rack without filter media.
Manual Damper – economizer is available with a
manual damper adjustable between 0-25 percent.
Two-Position – economizer is available with a
two-position damper with the open position manually
adjustable between 0-25 percent. It is controlled via the
occupied/unoccupied signal from the unit controller. In
occupied mode, the economizer will be open and in the
unoccupied mode, the dampers will be closed.
0-100% Modulating – modulating control of exhaust
air to maintain building static pressure. Outdoor air and
return air dampers are interlocked and positioned by
fully modulating, solid state damper actuators. Control
of the damper is via a dry bulb sensor, single or comparative enthalpy .
Airflow Measurement – airflow measurement is available for the Modulating Damper Economizer option listed
above. Three options exist for airflow measurement;
minimum, full and 25%/75% airflow. Minimum airflow
measures airflow between 0 and the minimum ventilation airflow up to 25% outside air. 100% airflow measurement measures air flow from 0-100% of the outside
airflow. A third option includes a two-stage airflow measurement; stage one 0-25% and stage two 25-100%.
2
CO
Sensors – carbon dioxide sensors for occupied
space that operate demand ventilation control opening
outside air dampers to ventilate building. A vailable with
0-100% modulating economizer.
RELIEF SYSTEM
to the building pressure. The opening pressure shall
be adjustable.
Power Exhaust – exhaust control options are on/off,
modulating discharge damper, or VFD fan speed control. On units with non-modulating exhaust a barometric relief damper is included to prevent outside air from
entering in the off cycle. Fans shall cycle on and off
with building pressure. (On units with modulating exhaust, a field-installed static pressure sensor mounted
in the conditioned space or return air duct is required
for damper and VFD modulation.)
EV APORATOR COIL PROTECTION
Copper Fins – provided in lieu of aluminum fins.
Pre-Coated Fins – an epoxy-coated aluminum fin stock
to guard from corrosive agents and insulate against
galvanic potential. Used for mild seashore or industrial
locations.
CONDENSER COIL PROTECTION
Copper Fins – provided in lieu of aluminum fins.
Pre-Coated Fins - an epoxy-coated aluminum fin stock
to guard from corrosive agents and insulate against
galvanic potential. Used for mild seashore or industrial
locations.
Post-Coated Fins – Technicoat coil-coating process
used on condenser coils for seashore and other corrosive applications (with the exception of strong alkalis,
oxidizers, wet bromide, chlorine and fluorine in concentrations greater than 100ppm).
REFRIGERANT SYSTEM OPTIONS
Hot Gas Bypass – Permits continuous, stable opera-
tion at capacities below the minimum step of compressor staging to as low as 5% capacity (depending on
both the unit and operating conditions) by introducing
an artificial load to the evaporator coil. Hot gas bypass
is standard on refrigerant system #1 on V A V units; available as an option on constant volume.
Replaceable Core Liquid Line Driers – liquid line driers are standard on the eco2 rooftop unit. An option is
provided for replaceable core driers.
Barometric Relief – building air exhaust shall be accomplished through barometric relief dampers installed
in the return air plenum. The dampers will open relative
YORK INTERNATIONAL
Compressor Isolation Valves – optional ball valves
installed in the compressor suction and discharge lines
allow easier access to the compressors without having to
remove the unit charge during compressor servicing.
75
Page 76
Guide Specifications (continued)
ROOF CURBS
Full Perimeter Roof Curbs – 14" high roof curb with wood
nailer. Roof curb supports the entire perimeter of the unit.
Partial perimeter roof curbs – 14" high roof curb with
wood nailer. Roof curb supports the air handling section with a separate support under the condenser end.
sound blankets for sound sensitive applications.
Filter Switch – an optional dirty filter alarm can be pro-
vided that will provide an alarm when the filters require
cleaning.
Return Air Temperature Sensor – this sensor when
ordered separately can be used for readout through
the OptiLogic controller, and it can be used as a backup
in the event space temperature sensor fails for temporary unit operation. For units supplied with a comparative enthalpy economizer control, this option is already
included. This sensor is included with heat options, and
optional for units with cooling options. This sensor must
be present for morning warm-up.
Condenser Coil Guard – this optional wire guard protects the condenser section from access and is used
for unit aesthetics.
Louvered Panels – Louvered panels surround the front,
back, and sides of the unit. These prevent unauthorized access and visually screen unit components. Unrestricted air flow is permitted through generously sized
louvered openings. This option is applicable for any
outdoor design ambient temperature up to 46.1°C. (Factory- or Field-mounted.)
SUPPLY F AN OPTIONS
Fan Skid Isolation – the entire supply fan assembly
shall be isolated from the unit base with two-inch deflection springs, or one or two-inch deflection springs
with seismic restraints.
Supply and Exhaust Fan Motors – high efficiency
ODP, standard and high efficiency TEFC motors are
available, all meeting the Energy Policy Act of 1992
(EPACT).
Supply Fan VFD and Manual Bypass – for VAV applications, VFDs are provided to modulate air flow. Optional manual bypass can also be provided to allow full
airflow in the event of a VFD failure.