Controls Upgrade Kit (036-150 Units) — The controls kit in-
cludes high-pressure, loss-of-charge/low-pressure, and freeze
protection cutout switches. The high-pressure and loss-of-
charge/low-pressure switches can be easily added by screwing
the switches onto Schrader-type fittings provided on the refrig-
erant lines.
SUGGESTED USE:
• Kit provides additional protection against system high pres-
sure, loss-of-charge/low pressure, and evaporator coil frost
build-up for 036-150 units.
NOTE: These switches are standard on the 180-300 units.
Condenser Coil Grille (036-150 units) — The grille protects
the condenser coil from damage and requires no additional
clearance.
SUGGESTED USE:
• When unit is located in high traffic areas or could be subject to
damage.
• As an alternate location for the field-supplied disconnect
switch.
FIELD-INSTALLED ACCESSORY
DESCRIPTION AND USAGE
Roof Curbs (Vertical and Horizontal) — Full-perimeter galva-
nized steel support frame in 14- and 24-in. high designs pro-
vides wood nailer to attach roof counter flashing. Insulated
basepans in curb are provided to prevent condensation. Duct-
work attaches to rails provided in the roof curb. A gasket is pro-
vided to form an air- and watertight seal between unit and curb.
The gasket meets the standards of the NRCA (National Roofing
Contractors’ Association).
SUGGESTED USE:
• Rooftop application for vertical discharge.
• Slab-mounted applications when elevation of the unit is
necessary.
Horizontal Adapter (180-300 Units) — The curb is prefabri-
cated, easily field-assembled, and permits full perimeter mount-
ing. The curb also improves unit static performance by up to
0.6 in. wg.
SUGGESTED USE:
• Rooftop application for horizontal discharge on 180-300 units.
• Rooftop applications for horizontal discharge on 180-300
units where high air delivery cfms are required.
Condenser Coil Hail Guard (036-150 Units) — Package con-
sists of a hood and coil grille which attach to the condenser coil.
SUGGESTED USE:
• To protect the condenser coil from hail and other debris on
036-150 units.
• As an alternate location for field-installed disconnect switch.
Condenser Coil Grille (036-150 Units) — The grille protects
the condenser coil from damage and requires no additional
clearance.
SUGGESTED USE:
• When unit is located in high traffic areas or could be subject to
damage.
• As an alternate location for the field-supplied disconnect
switch.
25% and 50% Manual Outdoor-Air Dampers (036-150 Units)
— Package consists of a damper which can be set at either
25% or 50% outdoor air (as appropriate). The package includes
a rainhood, birdscreen, and a panel with a hole in it for easy
installation.
SUGGESTED USE:
• To allow a fixed percentage of outdoor air for ventilation under
all conditions.
• The damper may be used on either vertical or horizontal
applications.
Two-Position Dampers — Package consists of a low-leak
damper assembly and a panel with a hole in it for easy instal-
lation (036-150 units). The damper will allow either 0 or 25% or
100% (depending on accessory package) outdoor air into the
unit any time the evaporator fan is running, and features close-
on-power-loss. When the evaporator fan is off, the damper will
be closed.
SUGGESTED USE:
• Allows a fixed percentage of outdoor air any time the evapo-
rator fan is on, but closes when the evaporator fan is off to
prevent cold backdrafts and wasted energy.
• The damper may be used on either vertical or horizontal air-
flow applications.
Economizers — See descriptions listed under Factory-
Installed Options Description and Usage section on page 2.
NOTE: When the accessory Durablade economizer is ordered
for the 036-150 units, the package also contains an outdoor-air
panel for easy installation.
Solid-State Enthalpy Control (036-150 Units) — Package
consists of a solid-state control and sensor which is capable of
sensing outdoor-air heat content (temperature and humidity)
and controlling economizer cut-in point to have minimum heat
content air passing over the evaporator coil. The solid-state en-
thalpy control replaces the standard dry-bulb thermostat in the
economizer.
SUGGESTED USE:
• To enhance economizer operation for additional energy
savings.
Enthalpy Control Sensor — Package consists of a solid-state
sensor to be used in conjunction with the solid-state enthalpy
control (036-150 units) or paired with a second enthalpy sensor
(180-300 units) for differential enthalpy control. This sensor is
mounted on the economizer assembly so that it can sense
building temperature. The 2 sensors will determine which com-
bination of outdoor and return air will provide the greatest en-
ergy savings.
SUGGESTED USE:
• To enhance economizer operation for maximum energy
savings.
NOTE: On 180-300 units, a single sensor may be used for
single-sensor, outdoor-air enthalpy control if desired.
Time Guardா II Device — Package consists of a control to be
field wired into the unit controls, and provides a 5-minute delay
in compressor operation between cooling cycles.
SUGGESTED USE:
• Prevents compressor short cycling when rapid compressor
cycles may be a problem.
Controls Upgrade Kit (036-150 Units) — See description
listed under Factory-Installed Options Description and Usage
section on page 2.
Fan/Filter Status (036-150 Units) — Provides status of indoor
(evaporator) fan (ON/OFF) or filter (CLEAN/DIRTY). Status
shall be displayed with a field-supplied indicator light at the
thermostat.
SUGGESTED USE:
• To assist in servicing the unit.
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