Compressor Wire Routing - Emerson Comfort Alert 543-0033-00 User Manual

Compressor Wire Routing (Figure 3)
The scroll compressor's run (R), common (C) and start (S) wires are routed through the
holes in the Comfort Alert module marked "R," "C" and "S." The common (C) wire need
not be routed through the module for it to operate properly.
Thermostat Demand Wiring
The Comfort Alert module requires a thermostat demand signal to operate properly. The
thermostat demand signal input, labeled Y on the module, should always be connected
to the compressor contactor coil so that when the coil is energized, the demand signal
input is 24VAC. When the coil is not energized, the demand signal input should be less
than 0.5VAC.
NOTE: Factory installed modules may have different thermostat demand signal
wiring. Follow manufacturer's wiring instructions when replacing module.
NOTE: After the thermostat demand signal is connected, verify Y is phased
properly with C by measuring 24VAC across Y and C when demand is present.
4
Figure 3
24VAC Power Wiring
The Comfort Alert module requires
a constant nominal 24VAC power
supply. The wiring to the module's R
and C terminals must be directly from
the indoor unit or thermostat. The
module cannot be powered by the C
terminal on a defrost board or other
control board without experiencing
nuisance alerts. Refer to Figure 5.
When constant 24VAC (R wire) is not
present in the outdoor unit, use one of
the spare wires in the thermostat cable
to bring power to the module. Connect
the other end of the spare wire to R at
the indoor unit or thermostat. Refer to
wiring schematic in Figure 4 and 5.