152
JOHNSON CONTROLS
5276178-JIM-C-0118
Sequence of Operation
•
The W1 low heat input is lost or the Morning
Warm Up command from a BAS system is lost.
Sequence of Operation
1. The return fan starts.
2. After 5 minutes the Unit Control compares the
Return Air Temperature to the “RAT HEATING
SETPOINT”.
3. If the Return Air Temperature is greater than the
“RAT HEATING SETPOINT” minus 1.0°F the
Unit Control will not energize the heating se-
quence.
4. If the Return Air Temperature is less than or
equal to the “RAT HEATING SETPOINT” minus
1.0°F the Unit Control will energize the heating
sequence.
5. The Unit Control sets the “SUPPLY AIR TEMP
ACTIVE SP” as follows:
a) Variable Air Volume and FlexSys units minus
“HEATING SAT”.
b) CONSTANT VOLUME units minus “2ND
STAGE HEATING SET POINT”.
6. The heat source remains energized until the Return
Air Temperature is greater than or equal to the
“RAT HEATING SET POINT” plus 0.5°F, or the
morning warm up command is removed, or the
unit switches to occupied mode.
ADAPTIVE MORNING WARM UP
Adaptive Morning Warm Up can only be used when
the internal Schedule function is employed to switch
the unit from Unoccupied to Occupied mode. The Unit
Control calculates the start time for the heat to ensure
the Return Air Temperature is within 0.5°F of the
“RAT
HEATING SETPOINT”
when the unit switches to the
occupied mode. To do this the Unit Control calculates
the
“MORNING WARM UP OPT TIME”
by averaging
the time it takes to bring the
“RETURN AIR TEMP”
to
within 0.5°F of the
“RAT HEATING SETPOINT”
for
three consecutive days. The three warm up times are
averaged and added to a 10 minute offset. The new time
is used as the
“MORNING WARM UP OPT TIME”
for
the next day.
In order to use Adaptive Morning Warm Up the Primary
Control must be configured as follows:
•
The
“OCCUPANCY SCHEDULE”
must be pro-
grammed for the Occupied, Unoccupied start and
stop times. This is done through the SCHEDULE
key of the User Interface.
•
The
“OCCUPANCY SCHEDULE”
must be
USER ENABLED. This is done through the
SCHEDULE key of the User Interface.
•
“MORNING WARM UP”
must be set to USER
ENABLED. This can be done through the PRO-
GRAM key, HEATING subsection of the User
Interface.
•
“ADAPT MORN WARM UP”
must be set to
USER ENABLED. This can be done through
the PROGRAM key, HEATING subsection of
the User Interface.
•
“RAT HEATING SETPOINT”
must be set.
This can be done through the SETPOINTS key,
HEATING subsection of the User Interface.
•
“MORNING WARM UP MAX TIME”
must be
set. This can be done through the SETPOINTS
key, HEATING subsection of the User Inter-
face.
The following limitations apply:
•
If the
“MORNING WARM UP OPT TIME”
ex-
ceeds the
“MORNING WARM UP MAX TIME”
the
“MORNING WARM UP OPT TIME”
shall
be
“MORNING WARM UP MAX TIME”
.
•
If the
“MORNING WARM UP OPT TIME”
is determined to be less than 15 minutes, the
“MORNING WARM UP OPT TIME”
shall be
set to 15 minutes.
•
The default values for
“DAILY WARM UP TIME
DAY 1”, “DAILY WARM UP TIME DAY 2”,
and
“DAILY WARM UP TIME DAY 3”
shall initially
be set at 60 minutes. These values can be reset to
the default values by turning the
“MORN WARM
UP”
to USER DISABLED and then back USER
ENABLED.
Sequence of Operation
1. The return fan starts.
2. After 5 minutes the Unit Control compares the
Return Air Temperature to the “RAT HEATING
SETPOINT”.
3. If the Return Air Temperature is greater than the
“RAT HEATING SETPOINT” minus 1.0°F the
Unit Control will not energize the heating sequence
and it sets the daily warm up time to 5 minutes.
4. If the Return Air Temperature is less than or
equal to the “RAT HEATING SETPOINT” minus
Summary of Contents for 40 25 TON
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