528195-YTG-I-0513
10
Johnson Controls Unitary Products
Unit Controls:
a. Unit shall be complete with self-contained low-voltage
control circuit protected by a resettable circuit breaker on
the 24-volt transformer side.
b. Unit shall incorporate a lockout circuit which provides
reset capability at the space thermostat or base unit
should any of the following standard safety devices trip
and shut off compressor:
c. Loss-of-charge/Low-pressure switch.
• High-pressure switch.
• Freeze-protection thermostat, evaporator coil. If any of
the above safety devices trip, an LED (light-emitting
diode) indicator shall flash a diagnostic code that
indicates which safety switch has tripped.
d. Unit shall incorporate “AUTO RESET” compressor over
temperature, over current protection.
e. Unit shall operate with conventional thermostat designs
and have a low voltage terminal strip for easy hook-up.
f. Unit control board shall have on-board diagnostics and
fault code display.
g. Standard controls shall include anti-short cycle and low
voltage protection, and permit cooling operation down to
0 ºF.
h. Control board shall monitor each refrigerant safety switch
independently.
i. Control board shall retain last 5 fault codes in non-
volatile memory, which will not be lost in the event of a
power loss.
ELECTRIC HEATING SECTION (IF EQUIPPED)
An electric heating section, with nickel chromium elements,
shall be provided in a range of 9 thru 54 KW, offering two states
of capacity all sizes. The heating section shall have a primary
limit control(s) (automatic reset) to prevent the heating element
system from operating at an excessive temperature. The Heat-
ing Section assembly shall slide out of the unit for easy mainte-
nance and service. Units with Electric Heating Sections shall be
wired for a single point power supply with branch circuit fusing
(where required).
UNIT OPERATING CHARACTERISTICS
Unit shall be capable of starting and running at 125 ºF outdoor
temperature, exceeding maximum load criteria of AHRI Stan-
dard 340/360. The compressor, with standard controls, shall be
capable of operation down to 0 ºF outdoor temperature.
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,
Elect. Heat Elem. – 5 Years, Parts – 1 Year
FACTORY INSTALLED 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 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 ºF. 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.
Available with barometric relief or power exhaust.
•
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.
ADDITIONAL FACTORY INSTALLED OPTIONS
•
ALTERNATE INDOOR BLOWER MOTOR
– For
applications with high restrictions, units are available with
optional indoor blower motors that provide higher static
output and/or higher airflow.
•
CONVENIENCE OUTLET (POWERED/NON-POWERED)
–
Unit can be provided with an optional 120VAC GFCI outlet
with cover on the corner of the unit housing the compressors.
•
ELECTRIC HEAT
- Electric Heaters range from 9 kW to
54 kW and are available in all the voltage options of the
base unit.
•
PHASE MONITOR
- Designed to prevent damage in out-
of-phase condition.
•
COIL GUARD
- Designed to prevent condenser coil
damage.
•
BAS CONTROLS
- Include supply air sensor, return air
sensor, dirty filter indicator and air proving switch.
