Sequence Of Operation - KMC Controls KMCConquest FlexStat BAC-19 Series Sequence Of Operation

SEQUENCE OF OPERATION:

1. Occupancy: The occupancy mode follows the internal schedule. If motion
(optional) is not sensed within the standby timer during occupied mode,
the unit goes into standby mode until motion is sensed again.
2. On/off fan: When the fan mode is set to Auto and heating (any form),
cooling or economizer is called for, the fan starts. Once the space temp
returns to setpoint, there is no call for any heating, cooling nor economizer
and the fan-off-delay expires (2 minutes), the fan shuts off. During the
occupied and standby modes, the fan output is energized any time the fan
mode is set to On.
3. When the fan starts, if the normally closed fan status switch (optional)
doesn't open within 10 seconds, all heating, cooling and economizer
outputs are deenergized.
heating/cooling/economizer outputs remain disabled until the fan status
switch opens.
4. Reversing valve: The reversing valve output is energized on a call for
cooling (adjustable).
6. Cooling: As space temp rises above the cooling setpoint plus the cooling
span, compressor 1 is energized if the minimum off time has been met. If
the space temp remains above the cooling setpoint plus the cooling span
for the stage delay, compressor 2 is energized after ensuring its minimum
off time. As the space temp drops below half of the cooling span above
the cooling setpoint, compressor 2 is deenergized. As the space temp
drops below the cooling setpoint, compressor 1 is deenergized.
7. Compressor heating: As space temp drops below the heating setpoint
minus the heating span, compressor 1 is energized if the minimum off time
has been met. If the space temp remains below the heating setpoint
minus the heating span for the stage delay, compressor 2 is energized
after ensuring its minimum off time. As the space temp rises above half of
the heating span below heating setpoint, compressor 2 is deenergized. As
the space temp rises above the heating setpoint, compressor 1 is
deenergized.
8. Auxiliary heat/third stage: When auxiliary heat is configured for Third
Stage, the unit is in heating mode and compressor 2 has been on for the
stage delay, the aux heat output is energized. As the space temp rises
above 65% of the heating span below heating setpoint, aux heat is
deenergized.
COMP 1/
REV
VALVE
CLG
SP
COMPRESSOR HEATING/AUX HEAT-3RD STAGE OPERATION
COMP 1
COMP 2
(STAGE
DELAY)
AUX HT-
3RD STAGE
(STAGE
DELAY)
2.0F
2.0F
© 2020 KMC CONTROLS, INC.
BAC-19xxxx FlexStat Sequence of Operation and Wiring Guide
Heat Pump Unit with Auxiliary Heat,
Economizer, and Humidity, Motion and CO2 Sensors
Model: BAC-19xx63C(E)
The fan output remains enabled and
COOLING STAGES OPERATION
COMP 1/
COMP 2
REV
VALVE
COMP 2
(STAGE
DELAY)
ROOM TEMP INCREASE
1.0F 2.0F
COMP 2
AUX HT-
3RD
COMP 1
STAGE
ROOM TEMP INCREASE
1.0F HTG
SP
AUX HEAT-COMPRESSOR LOCKOUT/
EMERGENCY HEAT OPERATION/
AUX AUX
HEAT HEAT
(NOTE: COMPRESSORS
ARE LOCKED OUT)
ROOM TEMP INCREASE
1.0F HTG
SP
19476 INDUSTRIAL DR.
DRAWING TITLE:
NEW PARIS, IN 46553
PHONE: 574.831.5250 CREATION DATE:
FAX: 574.831.5252
REVISION DATE:
kmccontrols.com
9. Auxiliary heat/compressor lockout: When auxiliary heat is configured for
Comp Lockout, both compressors are locked out and the auxiliary heat
output follows the compressor 1 heating sequence.
10. Emergency heat: When the system mode is manually set to Emergency
Heat, all outputs besides fan are locked out and aux heat is energized as
space temp drops below heating setpoint minus heating span. As the
space temp rises above the heating setpoint, the aux heat output is
deenergized.
11. Economizer: During occupied mode, if outside air temp (OAT) drops
below the economizer enable temp and there is a call for cooling, econ
mode is enabled. Econ mode is disabled if OAT rises 1 deg above the
econ enable temp. While economizing, the outside air damper (OAD)
modulates to maintain discharge air temp (DAT). As space temp rises
above the cooling setpoint, DAT setpoint resets from the space temp to
the minimum DAT. While economizing, the OAD is open to the greater of
the minimum damper position or DAT control. The OAD is shut during
unoccupied mode and any time the fan is off.
12. If the space humidity (optional) rises above the dehumidification setpoint,
compressor 1 is energized if the minimum off time has been met. If the
humidity remains high for the stage delay and compressor 2's minimum off
time has been met, compressor 2 is energized.
cycled to maintain the COOLING setpoint. Once the space humidity drops
below the dehumidification setpoint minus its span, dehumidification
ceases and the compressors resume normal space temp control.
13. In Basic Demand Control Ventilation (DCV), the OA damper opens 100%
as the CO2 level rises above the CO2 setpoint. As the CO2 level drops
below the CO2 setpoint minus the CO2 deadband, the damper
relinquishes to previous control.
14. In Standard DCV, the OA damper modulates from 0% open as the CO2
level rises from the CO2 base level +200 ppm to 100% open at the CO2
base level +600 ppm.
15. When both CO2 and economizer control are enabled, the damper
responds to the greater of CO2 or economizer control.
ROOM TEMP
MIN DAT
CLG
SP
DEHUMIDIFICATION OPERATION
AUX
HEAT
HTG SPAN
-2F
ON
AUTO
OFF
HTG SPAN
-2F
17
FILENAME: KH19001-2
1/2/2020
1/31/2020 REVISION: INITIAL RELEASE
Auxiliary heat is then
ECONOMIZER DAT SETPOINT
CLG SPAN ROOM
TEMP
+2F
INCREASE
COMP 1/
REV
COMP 1
VALVE
AUX
COMP 2
HEAT
REV
COMP 2
VALVE
(STAGE
DELAY)
ROOM TEMP DEHUM DIFF ROOM HUM
INCREASE INCREASE
CLG -5% DEHUM
SP SP
FAN OPERATION
AUTO AUTO
ON (ECON)
CLG SPAN ROOM
TEMP
HTG CLG +2F
INCREASE
SP SP
AG200123C