Fantech SHR450 Manuel D'installation page 19

WIRING DIAGRAM
WIRING DIAGRAM TO
FURNACE
ALTERNATE FURNACE
CONNECTION:
On some newer furnaces and older
thermostats, energizing the R and G
terminal at the furnace has the effect
of energizing the Y at the thermostat
and thereby turning on the cooling
system. If you identify this type of
thermostat, you must use the
"Alternate Furnace Interlock Wiring"
As per building codes and installation requirements for combustion appliances:
Air return ducts, or openings for air return, should not be placed in enclosed spaces containing combustion
appliances that are subject to spillage.
(CONT'D)
Alternate Furnace Interlock Wiring
FOUR
WIRE
TWO WIRE
heating only
W
R
G
C
Y
FURNACE
24-VOLT
TERMINAL BLOCK
TWO
WIRE
Alternate Furnace Interlock Wiring (w/Damper)
FOUR
WIRE
TWO WIRE
heating only
W
R
G
C
Y
FURNACE
24-VOLT
TERMINAL BLOCK
TWO
WIRE
THERMOSTAT
TERMINALS
R G
W Y
COOLING SYSTEM
THERMOSTAT
TERMINALS
W R G
Y
COOLING SYSTEM
COM
CONTROL RELAY
(TERMINAL LABELING MAY VARY)
RV-CTRL
24VAC
RV-CTRL
24VAC
C
SHUTOFF SHUTOFF
DAMPER DAMPER
NO
NC
COIL
19
R