York DH 300 - Manual (Page 43)

262260-YTG-E-1008
Johnson Controls Unitary Products 43
controls, shall be capable of operation down to 0° F outdoor
temperature. 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 ECONO-
MIZER - Outdoor and return air dampers that are inter-
locked 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 potenti-
ometer 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 condi-
tioned space during normal operation. During econo-
mizer 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 oper-
ation shall be provided by an integral electronic enthalpy
control that feeds input into the basic module. The out-
door intake opening shall be covered with a rain hood
that matches the exterior of the unit. Water eliminator/fil-
ters shall be provided. Simultaneous economizer/com-
pressor 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 maxi-
mum 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-Com-
fort™ control, free-cooling shall be available while the
outdoor dry bulb temperature (OAT) remains below a
programmable set-point of the controller. Field-installed
humidity sensors for either outdoor air or outdoor &
return air streams are available to provide free-cooling
based on single-enthalpy or dual-enthalpy configura-
tions, respectively. If free-cooling is available, a call for
cooling shall modulate the economizer in order to main-
tain a supply air temperature (SAT) programmable set-
point. With the use of a field-installed indoor air quality
sensor, the controller shall provide Demand Ventilation
by modulating the economizer dampers to allow more
outside airflow upon detection of elevated indoor CO
2
concentrations above a programmable set-point. With an
additional field-installed outdoor air quality sensor, Differ-
ential 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 maxi-
mum leakage rate for the outdoor air intake dampers shall
not exceed 2% when dampers are fully closed and operat-
ing 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 require-
ments 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-ener-
gized. 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 mount-
ing 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.