
PROCEDURE 9—SEQUENCE OF OPERATION
A.
Continuous Fan
Thermostat closes R to G. G energizes fan relay on PCB which completes circuit to indoor blower motor. When G is de-energized, there is a 90
sec delay before relay opens.
B.
Cooling Mode
Thermostat energizes R to G, R to Y, and R to O (heat pump only). G energizes fan relay on PCB which completes circuit to indoor blower motor.
When G is de-energized, there is a 90 sec delay before fan relay opens.
C.
Heat Pump Heating Mode
Thermostat energizes R to G and R to Y. G energizes fan relay on PCB which completes circuit to indoor blower motor. When G is de-energized,
there is a 90 sec delay before fan relay opens.
D.
Heat Pump Heating with Auxiliary Electric Heat
Thermostat energizes R to G, R to Y, and R to W. G energizes fan relay on PCB which completes circuit to indoor blower motor. W energizes
electric heat relay(s) which completes circuit to heater element(s). When W is de-energized, electric heat relay(s) open, turning off heater elements.
When G is de-energized there is a 90 sec delay before fan relay opens.
E.
Electric Heat or Emergency Heat Mode
Thermostat closes R to W. W energizes electric heat relay(s) which completes circuit to heater element(s). Blower motor is energized through
normally closed contacts on fan relay. When W is de-energized, electric heat relay(s) opens.
START-UP PROCEDURES
Refer to outdoor unit Installation Instructions for system start-up instructions and refrigerant charging method details.
Fig. 19—Insufficient Condensate Trap
A03013
DO NOT USE SHALLOW RUNNING TRAPS!
Fig. 20—Condensate Trap and Unit
A03003
FILTER
ACCESS
PANEL
SECONDARY DRAIN WITH
APPROPRIATE TRAP REQUIRED
(USE FACTORY KIT OR
FIELD-SUPPLIED TRAP)
PRIMARY TRAP REQUIRED
(USE FACTORY KIT OR
FIELD-SUPPLIED TRAP OF
SUFFICIENT DEPTH.
STANDARD P-TRAPS ARE
NOT SUFFICIENT. SEE
FIGURE OF RECOMMENDED
CONDENSATE TRAP)
—13—