Carrier 12 Installation And Service Instructions Manual page 18

AVERAGE OUTDOOR-AIR TEMPERATURE GREATER THAN OAT SETTING
Thermostat Demand G
Second Stage Cooling X
First Stage Cooling X
Deadband (Offset)
First Stage Heating
Second Stage Heating
AVERAGE OUTDOOR-AIR TEMPERATURE LESS THAN OAT SETTING, BUT GREATER THAN −2 C (28 F)
Thermostat Demand G
Second Stage Cooling X
First Stage Cooling X
Deadband(Offset)
First Stage Heating
Second Stage Heating
AVERAGE OUTDOOR-COIL TEMPERATURE LESS THAN −2C (28 F)
Thermostat Demand G
Second Stage Cooling X
First Stage Cooling X
Deadband (Offset)
First Stage Heating
Second Stage Heating
AVERAGE OUTDOOR-COIL TEMPERATURE GREATER THAN −2 C (28 F)
Thermostat Demand G
Second Stage Cooling X
First Stage Cooling X
Deadband (Offset)
First Stage Heating
Second Stage Heating
Fig. 20 — Typical Operating Sequence
NOTES:
1. In heating mode, economizer damper blade will move to the mini-
mum position, and unit will operate as described for units without
economizer, regardless of outdoor air temperature.
2. The temperatures given in the graph are for demonstration pur-
poses only and may vary depending on which thermostat is used.
UNITS WITH ECONOMIZER
Y1 Y2 W1 W2 C1
X X X
X X
X X
X X X
Y1 Y2 W1 W2 C1
X X X
X
X X
X X X
UNITS WITHOUT ECONOMIZER
Y1 Y2 W1 W2 C1
X X X
X X
X X
X X X
Y1 Y2 W1 W2 C1
X X X
X X
X X
X X X
18
LEGEND
C — Contactor
HC — Heater Contactor
IFC — Indoor-Fan Contactor
OAT — Outdoor-Air Thermostat
OFC — Outdoor-Fan Contactor
RVS — Reversing Valve Solenoid
W — Heating Stage
X — Contact Energized
Y — Cooling Stage
C2 IFC OFC RVS1
X X X X
X X X
X X
X X X
C2 IFC OFC RVSI
X X X
X X
X X
X X X
C2 IFC OFC RVSI
X X X X
X X X
X X
X X X
C2 IFC OFC RVSI
X X X X
X X X
X X
X X X
RVS2 HC
X
X
RVS2 HC
X
X
RVS2 HC
X
X
RVS2 HC
X
X