York J Series, Руководство пользователя

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JOHNSON CONTROLS
20
FORM 100.50-NOM7 (808)
Unit Sequence of Operation
As the Heating Stages are de-energized, or if steps of
heat should be dropped due to Excessive SAT (supply
air temperature), the steps of heat will be de-energized
one at a time. If the unit is not equipped with heat, the
control will ignore the W1 and W2 inputs.
Gas or Electric (Stepped) Heating
If the controller is configured for staged heating, the con -
troller will read the Heat Stages configuration setting to
determine the number of heating stages available. Gas
Heat can have up to three stages for 40-ton. Electric
can have up to 2 stages (80 and 108 kW)
Hydronic Heat
If the controller is configured for hydronic heat, the
controller will modulate the Hydronic Valve output to
maintain a Supply Air Temperature setpoint. The SAT
will be controlled as follows:
• W1 Active Only – Heat controlled to First Stage
SAT Setpoint.
• W1 and W2 Active – Heat controlled to Second
Stage SAT Setpoint.
• W2 w/o W1 – Heat controlled to Second Stage SAT
Setpoint.
Space Sensor Control (RTD)
Under space sensor control, the controller will monitor
the space temperature via the space sensor inputs and the
Occupied input and control the unit accordingly. The use
of a space sensor on a constant volume unit requires an
unoccupied/occupied signal to the controller. This sig-
nal can be received from one of three sources: the hard-
wired Unoccupied/Occupied input, internal scheduling,
or via a Network (BAS). The unoccupied/occupied
signal determines what programmed space temperature
setpoint to maintain in the controlled space.
For this option to function, the configuration setting
Space Sensor Enable must be set to ON and the sensor
must be reliable. During this mode of operation, if the
space sensor becomes unreliable, a fault will be gener-
ated. With this, the unit will shut down unless a RAT
(return air temperature) sensor is enabled and reliable.
If a RAT sensor is present, the unit will monitor the
Return Air Temperature for unit control decisions. If
the RAT sensor then becomes unreliable, the unit will
be shut down.
Types of Space Sensors
No Sensor – The configuration setting, Space Sensor
Enable, Must be selected OFF. The Control will only
operate the unit from the Thermostat inputs or from a
network (BAS).
Sensor Only – This sensor only has an RTD in it for
unit operation.
Sensor with Unoccupied Override Button – This Sen-
sor has an RTD and an Override button that shorts the
Sensor when pushed. After the Override button has been
pushed for a minimum of one second the unit will go
into the Unoccupied Override mode for the Unoccupied
Override Time. The Override mode is cleared if the unit
goes Occupied during this Override mode.
Sensor with Space Setpoint Adjust – This Sensor has a
slider potentiometer on it that represents (as a default)
± 3°F adjustment to the Space Setpoint. The Space
Setpoint Offset Setpoint specifies the amount of ± ad -
justment, in range from 0°F to 5°F.
Sensor w/ Space Setpoint Adjust and Unoccupied Over -
ride Button – This Sensor has a slider potentiometer and
an Unoccupied Override button. Both functions operate
as described above.