FORM 100.50-NOM7 (808)
25
JOHNSON CONTROLS
3
• The programmable parameter
VAV Occupied Heat
-
ing
must be set to ON to enable the Occupied Heat-
ing With A Space Sensor function.
• The stepped heating control algorithm is:
• Turned ON when the space temperature is less
than the (VAV Setpoint for SAT Reset – 2°F).
• Controls the RAT between the Morning Warm
Up Setpoint and the (Morning Warm Up Setpoint
– 2°F).
(See Fig. 8).
• Turned OFF when the space temperature greater
than (VAV Setpoint for SAT reset - 1.5°F).
• Figure 12 illustrates the algorithm for occupied
heating required.
• For hydronic heating:
• The SAT is controlled to the 2
nd
Stage Hydronic
Heat Setpoint.
• The Heat 1 output of the controller is set to con-
trol HIGH during heating.
Unoccupied Heating With A Space Sensor
• The programmable parameter
VAV Operation with
Thermostat
must be set to OFF and Space Sensor
signal must be reliable.
• For hydronic heating:
• The SAT is controlled to the 2
nd
Stage Hydronic
Heat Setpoint.
• The Heat 1 output of the controller is set to con-
trol HIGH during heating.
Occupied Cooling With A Space Sensor
• The programmable parameter
VAV Operation with
Thermostat
must be set to OFF and Space Sensor
signal must be reliable.
• The SAT setpoint for cooling is the VAV Cool
Low Temperature Setpoint or VAV Cool High
Temperature Setpoint through comparison of the
space temperature and the VAV Setpoint for SAT
Reset as shown in Figure 12.
Unoccupied Cooling With A Space Sensor
• The programmable parameter
VAV Operation with
Thermostat
must be set to OFF and Space Sensor
signal must be reliable.
• Cooling is called for according to the algorithm
illustrated in Figure 10.
FIG. 8 – VAV OCCUPIED HEATING TO MAINTAIN
RAT AND MORNING WARM UP
All heating steps
sequentially added
All heating s
dropped
MWU Setpoint
RET URN AIR TEM PER ATURE (˚F)
-2.0
O N
O FF
LD06557
• The programmable parameter
VAV Occupied Heat
-
ing
must be set to ON to enable the Occupied Heat-
ing With A Space Sensor function.
• The space temperature is controlled to the Unoc-
cupied Heating Setpoint using the algorithm illus-
trated in Figure 9.
FIG. 9 – VAV UNOCCUPIED STEPPED HEATING
TEMPERATURE CONTROL
LD06558
All heating s
dropped
SPA CE TEMPERA TURE (˚F)
-0.5˚F
+0.5˚F
UNOCC . HTG. SETPOINT
All heating steps
sequentially added
ON
OFF
Summary of Contents for J Series
Page 85: ...FORM 100 50 NOM7 808 85 JOHNSON CONTROLS 6 ELECTRICAL NOTES AND LEGEND LD13862 ...
Page 87: ...FORM 100 50 NOM7 808 87 JOHNSON CONTROLS 6 LD13864 ...
Page 88: ...JOHNSON CONTROLS 88 FORM 100 50 NOM7 808 Service OPTI CONVERSION TO 25 40 TON LD13854 ...
Page 89: ...FORM 100 50 NOM7 808 89 JOHNSON CONTROLS 6 LD13865 ELEMENTARY DIAGRAM ALL UNITS ...
Page 91: ...FORM 100 50 NOM7 808 91 JOHNSON CONTROLS 6 ELEMENTARY DIAGRAM GAS HEAT 25 40 TON 575V LD13861 ...