York SUNLINE MAGNADRY WR 180 Technical Manual page 55

262292-YTG-C-0707
UNIT OPERATING CHARACTERISTICS
Unit shall be capable of starting and running at 125° F outdoor
temperature, exceeding maximum load criteria of ARI Standard
340/360. The compressor, with standard controls, shall be
capable of operation down to 25° F outdoor temperature.
Accessory low ambient kit shall be available for operation to 0°
F. Unit shall be provided with fan time delay to prevent cold air
delivery before heat exchanger warms up (Gas heat only).
ELECTRICAL REQUIREMENTS
All unit power wiring shall enter unit cabinet at a single factory
provided location and be capable of side or bottom entry, to
minimize roof penetrations and avoid unit field modifications.
Separate side and bottom openings shall be provided for the
control wiring.
STANDARD LIMITED WARRANTIES
• Compressor 5 Years
• Heat Exchanger 10 Years
• Electric Heat Element 5 Years
• Other Parts 1 Year
OPTIONAL OUTDOOR AIR (Shall be made available by
either/or):
• ELECTRONIC ENTHALPY AUTOMATIC ECONOMIZER
- Outdoor and return air dampers that are interlocked and
positioned by a fully-modulating, spring-return damper
actuator. The maximum leakage rate for the outdoor air
intake dampers shall not exceed 2% when dampers are
fully closed and operating against a pressure differential
of 0.5 IWG. A unit-mounted potentiometer shall be
provided to adjust the outdoor and return air damper
assembly to take in CFM of outdoor air to meet the
minimum ventilation requirement of the conditioned space
during normal operation. During economizer operation, a
mixed-air temperature control shall modulate the outdoor
and return air damper assembly to prevent the supply air
temperature from dropping below 55°F. Changeover from
compressor to economizer operation shall be provided by
an integral electronic enthalpy control that feeds input into
the basic module. The outdoor intake opening shall be
covered with a rain hood that matches the exterior of the
unit. Water eliminator/filters shall be provided.
Simultaneous economizer/compressor operation is also
possible. Dampers shall fully close on power loss.
• BAS-READY ECONOMIZER - Outdoor and return air
dampers that are interlocked and positioned by a fully-
modulating, spring return damper actuator. The maximum
leakage rate for the outdoor air intake dampers shall not
exceed 2% when dampers are fully closed and operating
against a pressure differential of 0.5 IWG.
For units with optional VAV or Simplicity® Intelli-Comfort™
control, free-cooling shall be available while the outdoor
dry bulb temperature (OAT) remains below a programma-
ble set-point of the controller. Field-installed humidity sen-
sors for either outdoor air or outdoor & return air streams
are available to provide free-cooling based on single-
Unitary Products Group
enthalpy or dual-enthalpy configurations, respectively. If
free-cooling is available, a call for cooling shall modulate
the economizer in order to maintain a supply air tempera-
ture (SAT) programmable set-point. With the use of a
field-installed indoor air quality sensor, the controller shall
provide Demand Ventilation by modulating the econo-
mizer dampers to allow more outside airflow upon detec-
tion of elevated indoor CO
programmable set-point. With an additional field-installed
outdoor air quality sensor, Differential Demand Ventilation
shall be provided.
The outdoor intake opening shall be covered with a rain
hood that matches the exterior of the unit. Water elimina-
tor/filters shall be provided.
Simultaneous economizer/compressor operation is also
possible. Dampers shall fully close on power loss.
• MOTORIZED OUTDOOR AIR DAMPERS - Outdoor and
return air dampers that are interlocked and positioned by
a 2-position, spring-return damper actuator. The
maximum leakage rate for the outdoor air intake dampers
shall not exceed 2% when dampers are fully closed and
operating against a pressure differential of 0.5 IWG. A
unit-mounted potentiometer shall be provided to adjust
the outdoor and return air damper assembly to take in the
design CFM of outdoor air to meet the ventilation
requirements of the conditioned space during normal
operation. Whenever the indoor fan motor is energized,
the dampers open up to one of two pre-selected positions
- regardless of the outdoor air enthalpy. Dampers return to
the fully closed position when the indoor fan motor is de-
energized. Dampers shall fully close on power loss.
OTHER PRE-ENGINEERED ACCESSORIES AVAILABLE
• ROOF CURB - 14" high, full perimeter curb with wood
nailer (shipped knocked-down).
• 100% BAROMETRIC RELIEF DAMPER - Contains a rain
hood, air inlet screen, exhaust damper and mounting
hardware. Used to relieve internal air pressure through
the unit.
• PROPANE CONVERSION KIT - Contains new orifices
and gas valve parts to convert from natural to L.P. gas.
One per unit required.
• HIGH ALTITUDE - NATURAL GAS - Contains orifices
required for applications between 2000 and 6000 feet
altitude.
• HIGH ALTITUDE - PROPANE GAS - Contains orifices
required for applications between 2000 and 6000 feet
altitude. Must be used with propane conversion kit.
• BURGLAR BARS - Designed to work with above roof
curbs, depending on unit model. Fits duct openings of
curb supply and return air openings.
• SIDE DUCT FLANGE - Supply and return air duct flanges
for side duct applications. Do not use on units with power
exhaust.
• HIGH STATIC DRIVE - May Include a belt, blower pulley,
motor pulley or a motor change to enhance blower
performance.
concentrations above a
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