AAON Mini Controller, Руководство пользователя, Страница: 35 / 52

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variable capacity scroll compressor is de-
activated.
Single Zone VAV Cooling Operation -
Supply Air Temperature Control
When the space temperature has deviated ½
of the space temperature deadband above the
cooling space temperature setpoint supply
air temperature control is activated. The
variable capacity scroll compressor is
activated at 100% for one minute, The
compressor then modulates to maintain the
cooling supply air temperature setpoint.
For heat pump units with the controller
configured for the reversing valve to be
activated during the cooling mode of
operation, all reversing valves are activated
along with the variable capacity scroll
compressor.
For units with two stage cooling, if the
variable capacity scroll compressor operates
at a maximum capacity for the compressor
stage delay amount of time and the supply
air temperature is increasing the second
compressor is activated and the variable
capacity scroll compressor modulates to
maintain the cooling supply air temperature
setpoint.
For units with two stage cooling, if the
variable capacity scroll compressor operates
at a minimum capacity for the compressor
stage delay amount of time and the cooling
supply air temperature is decreasing the
second compressor is de-activated. The
variable
capacity scroll compressor
modulates to maintain the cooling supply air
temperature setpoint.
As the space temperature achieves the
cooling space temperature setpoint minus ½
of the space temperature deadband supply
air temperature control is de-activated and
the variable capacity scroll compressor is
de-activated.
Constant Volume Heating Operation - Space
Temperature Control
When the space temperature has deviated ½
of the space temperature deadband below
the heating space temperature setpoint the
first stage of heating is activated.
If the space temperature remains ½ of the
space temperature deadband below the
heating space temperature setpoint for the
heating stage delay amount of time, if
available, the second stage of heating is
activated.
If the space temperature remains ½ of the
space temperature deadband below the
heating space temperature setpoint for
another heating stage delay amount of time,
if available, the third stage of heating is
activated.
When the space temperature reaches the
heating space temperature setpoint, the third
stage of heating, if available, is de-activated.
As the space temperature achieves the
heating space temperature setpoint plus ½ of
the space temperature deadband the first and
second stages of heating are de-activated.
Modulating/SCR electric heating operates as
a single stage of heating. Heating elements
modulate using a supply air temperature
sensor and setpoint potentiometer to meet a
specific supply air temperature setpoint.
Modulating natural gas heating operates as a
single stage of heating. Supply air
temperature setpoint must be set on the
MODGAS
board. See WattMaster
MODGAS Controller manual for
modulating gas heat operation.
Equipment
with Modulating Gas/SCR
Electric Heat will require an additional
supply air temperature sensor be field
installed for the modulating heating controls.