30
6.0 SEQUENCE OF OPERATION
Operation
6.1 Cooling Mode
When the 2-stage thermostat calls for the 1st stage
of cooling, the outdoor fan motor is energized and
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motor is energized. The system then provides cooling
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the thermostat calls for the 2nd stage of cooling, the
compressor shifts to the 2nd stage of capacity and
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1st and 2nd stages as directed by the thermostat.
When the call for cooling has ended or the thermostat
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and outdoor fan motor are de-energized, but the
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seconds to extract the residual cooling capacity in the
cold indoor coil before it stops.
NOTE:
2 and 3 ton models feature a 2 speed ECM
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1st stage cooling operation and high speed for 2nd
stage cooling operation. Standard single-speed PSC
motors are used on 4 and 5 ton models.
6.2 Heating Mode
When the heat pump thermostat is set to “heat” mode,
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heating position. When the 2-stage thermostat calls
for the 1st stage of heating, the system then provides
heating for the conditioned space. If the thermostat
calls for the 2nd stage of heating, the compressor
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es as directed by the thermostat. When the call for
heating has ended, the compressor and outdoor fan
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continues to operate for 30 – 45 seconds to extract the
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ing valve solenoid is de-energized. If the system is
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and there is a call for heating.
NOTE:
2 and 3 ton models feature a 2 speed ECM
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stage heating operation and high speed for 2nd stage
heating operation. Standard single-speed PSC mo-
tors are used on 4 and 5 ton models.
6.3 Supplemental Electric
Heat in Heating Mode
If the building load should exceed the heating capacity
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direct the air-handler to energize supplemental electric
heat as required to meet the building load as a 3rd
stage of heat. The compressor and outdoor fan
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heaters and higher, the electric heater elements
are split into 2 stages controlled by energizing the
W1 and W2 thermostat pigtails on the air-handler
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pigtails are connected together at the air-handler,
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pump heating mode. If the 1st stage of electric heat
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W2 thermostat pigtails on the air-handler should be
connected together to provide maximum supplemental
heat.
6.4 Dual Fuel Applications
– Heating Mode
If the building load should exceed the heat pump
heating capacity in extreme outdoor conditions, the
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furnace. An outdoor ambient temperature can be set
in dual fuel enabled thermostats to direct the system
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thermostat is set to the EMERGENCY HEAT mode,
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furnace.
