Johnson Controls L-Series, Инструкция по эксплуатации

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FORM 145.05-EG2 (618)
JOHNSON CONTROLS 73
HEATING (OPTIONAL)
Hot Water
Optional hot water heating shall include hot water coil installed in the coil section on the
leaving air side of the evaporator coil, and hot water piping and a motorized valve.
Hot water heating coils shall be constructed of seamless 0.50-inch outside diameter cop-
per tubing with a wall thickness of 0.016-inches. The copper tubes shall be mechanically
expanded to the aluminum fins. Coils shall be a 1 row with up to 12 fins per inch. The
circuiting of the coil shall be such to allow the lowest water pressure drop. Hot water coils
shall have a vent and drain. The coil shall be leak tested with high pressure air in a warm
water bath. Convenient access to the coil for inspection and cleaning shall be from both
sides of the unit. The coil shall be installed on the leaving side of the direct expansion coil,
in a draw-through position.
To control the water flow through the coil, a factory installed two-way modulating valve
package shall be provided. A valve package includes the valve, actuator, wiring, and pip-
ing internal to the unit. The piping connections shall be protruding through the unit roof,
located for easy connection to the building risers.
[A non-averaging type freezestat shall be factory installed. When the freezestat senses the
entering air temperature is below the set point, the unit shall be put into the unoccupied
mode and the hot water valve shall be signaled to drive 100% open.]
Electric Heat
Electric heat shall consist of electric heater located inside the unit at the unit supply air
outlet, electric power control components, and necessary controls. Each stage of electric
heat shall not exceed 17.5 kW.
Electric heater shall be in an 18-gage sheet metal frame and shall be made out of nickel
chromium resistance wire. The heater shall be protected by automatic thermal cutout and
manual thermal cutout. The cutouts and heater electrical connection shall be enclosed in a
junction box with a hinged cover.
Heater shall be protected by fuses not larger than 45 amps and complete with contactors.
The electric heater shall be controlled by the unit controller and staged as necessary.
Electric heat shall be enabled when none of the compressors are energized. Simultaneous
operation of compressors and electric heat shall not be permitted.
FAN SECTION
Supply Air Fan
A single supply fan shall be provided comprised of a medium pressure, single width,
and single-inlet (SWSI) centrifugal plenum fan wheel with airfoil blades. The fan wheel
shall be a minimum of Class II construction to handle over 6.0" total static pressure. The
fan wheel and blades shall be constructed of painted steel. The fan shall be secured to a
ground and polished solid steel shaft coated with rust inhibitor. The shaft shall be secured
and supported by two heavy-duty pillow-block type grease lubricated bearings. Bearing
diameter shall be the same size as the main shaft diameter. Bearings shall be sized to pro-
vide an L-50 life at 200,000 hours. The fan bearings shall have extended grease lines to a
common location.