JOHNSON CONTROLS
61
SECTION 5 – SEQUENCE OF OPERATION
FORM 100.50-NOM12
ISSUE DATE: 04/02/2019
5
OCCUPANCY/UNOCCUPANCY
DETERMINATION
• The Series 100 can operate in an Occ or Unocc
mode.
• Occ and Unocc modes have different sequences for
fan operation, cooling/heating operation, as well as
ventilation and exhaust sequences.
• Unit occupancy is determined in the same manner
for each of the three unit types.
Determining occupancy can be achieved in one of three
ways. They are listed below in order of priority. If there
is 24 VAC provided to the Occ terminal on CTB1, this
overrides any occupancy commands from the Internal
Clock Schedule or the BAS:
1.
Hardwired:
A 24 VAC input is provided to CTB1
at terminal Occ. Please note that the 24 VAC
MUST be provided by the Series 100 unit. This
is used with a device such as a timeclock or set of
contacts from a field installed relay.
2.
Internal Clock Schedule:
The unit is pro-
grammed for Occ/Unocc times using the internal
Time Clock.
3.
BAS Command:
A BAS provides an Occ/Unocc
signal to the Series 100 unit through a commu-
nicated command (
BACnet MS/TP point AV88 or
BV12 OCCUPNCY_CMD
).
NIGHT SET-BACK
• Night set-back allows for unocc cooling and heating
of the Series 100 unit.
• The IPU board must have a valid zone temperature
reading for night set-back to operate.
•
Night set-back works with all unit configurations.
• It is strongly recommended that if night set-back is
used on VAV and FlexSys configured units, all VAV
or underfloor boxes should be left open during the
Unocc mode.
Night Set-Back Setup
• Night set-back must be User Enabled in the PRO-
GRAM-UNIT DATA menu (on older software
versions, night set-back was located in the PRO-
GRAM-HEATING menu and could only be User
Enabled if the Series 100 unit had a heating source
installed).
• Unocc zone cooling/heating setpoints must be
entered in the SETPOINTS-COOLING or SET-
POINTS-HEATING menus.
Night Set-Back Sequence Of Operation
• The unit is in the Unocc Standby mode.
• The current zone temperature becomes 0.5°F
above the unocc zone cooling setpoint or 0.5°F
below the unocc zone heating setpoint.
• The IPU board starts the supply fan. The supply
fan is controlled per the unit configuration de
-
scribed later in this section.
• Once the air proving switch (APS) is made, the
IPU board stages ON cooling or heating as deter-
mined by the current zone temperature.
• Cooling and heating operation is controlled per
the unit configuration described later in this sec
-
tion.
CURRENT OPERATING MODE
• The Series 100 unit can operate in many different
modes.
• Cooling and heating operation is determined in
different ways for each unit type: SZVAV, VAV,
or Flexsys.
• Comfort ventilation cooling and heating is de-
scribed in the
Comfort Ventilation section on page
.
• Morning warm-up is described in the
•
Underfloor
temperature override is described in
the
• The current operating mode can be viewed in the
STATUS menu.
• The IPU board monitors switching from a Stand-
by mode to an Active Cooling or Heating mode.
The unit must be in Standby mode for 3 minutes
before switching to an Active Cooling or Heating
mode.