Hvac Wiring Diagrams - Aprilaire 8840 Safety & Installation Instructions

HVAC WIRING DIAGRAMS

FIGURE 14 – CONVENTIONAL HEAT/COOL SINGLE TRANSFORMER (USE JUMPER)
1
THERMOSTAT
2
3
FIGURE 15 – CONVENTIONAL HEAT/COOL TWO TRANSFORMER (REMOVE JUMPER)
1
THERMOSTAT
2
3
1 R AND C CAN BE
POWERED FROM THE
HVAC EQUIPMENT
TRANSFORMER OR ANY
OTHER CONSTANTLY
POWERED 24VAC
SOURCE.
8
C
TRANSFORMER
R
RC
RH
HC HP
W W
1st HEATING
W2 W2
2nd HEATING
W3 B
3rd HEATING
Y Y
1st COOLING
Y2 Y2
2nd COOLING
Y3 O
3rd COOLING
G G
FAN
L
C
EQ
1
TRANSFORMER
C
R
COOLING TRANSFORMER
RC
RH
HEATING TRANSFORMER
HC HP
W W 1st HEATING
W2 W2 2nd HEATING
3rd HEATING
W3 B
Y Y 1st COOLING
Y2 Y2 2nd COOLING
Y3 O 3rd COOLING
G G FAN
L
C
EQ
FIGURE 16 – HEAT PUMP SINGLE TRANSFORMER (USE JUMPER WIRE)
THERMOSTAT
90-1717
FIGURE 17 – HEAT PUMP TWO TRANSFORMER (REMOVE JUMPER WIRE)
THERMOSTAT
1
R AND C CAN BE
POWERED FROM THE
HVAC EQUIPMENT
TRANSFORMER OR ANY
OTHER CONSTANTLY
POWERED 24VAC
SOURCE.
90-1718
C
R
1
RC HEAT PUMP
2
TRANSFORMER
RH
3
HC HP
W W 1st HEATING
W2 W2 2nd HEATING
W3 B REVERSING VALVE
Y Y 1st COMPRESSOR
Y2 Y2 2nd COMPRESSOR
Y3 O
REVERSING VALVE
G G FAN
L FAULT DETECT
C
EQ
1
TRANSFORMER
C
R
1
HEAT PUMP TRANSFORMER
RC
2
RH
3
HEATING TRANSFORMER
HC HP
W W 1st HEATING
W2 W2 2nd HEATING
W3 B REVERSING VALVE
Y Y 1st COMPRESSOR
Y2 Y2 2nd COMPRESSOR
Y3 O REVERSING VALVE
G G FAN
L FAULT DETECT
C
EQ
90-1719
90-1720
9