Trane IntelliPak with Symbio 800, Инструкция по установке, эксплуатации и обслуживанию

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RT-SVX063G-EN 75
Space Temperature Control
Units
Single Zone VAV and Constant Volume Space Temperature
units use the Space Temperature Control sequence of
operation in Occupied Heat and Occupied Cool modes of
operation; however, the Discharge Air Control method is
used for all other modes. The table below summarizes
each mode of operation and the control method applied.
See Operating Modes section for more details
Table 32. Mode of operation and applied control method
Heat Cool Mode Control Method Discharge Air Temperature
Setpoint Space/Discharge Setpoints
Cool Space Temperature Control Calculated
(cascade) Space Temperature Setpoint Active
Discharge Air Temperature Setpoint
Active
Heat Space Temperature Control Calculated
(cascade) Space Temperature Setpoint Active
Discharge Air Temperature Setpoint
Active
Morning Warm Up Discharge Air Control Fixed Morning Warmup Setpoint
Discharge Air Heating Setpoint Active
Pre Cool Discharge Air Control Fixed Pre Cool Setpoint
Discharge Air Cooling Setpoint Active
Night Purge Discharge Air Control Fixed
Unoccupied Cool Discharge Air Control Fixed Unoccupied Cooling Setpoint
Discharge Air Cooling Setpoint Active
Unoccupied Heat Discharge Air Control Fixed Unoccupied Heating Setpoint
Discharge Air Heating Setpoint Active
Single Zone VAV
Single Zone VAV equipment is configured with a variable
speed supply fan that modulates with Space Temperature
Control to minimize fan energy while maintaining space
comfort. When there is no demand for heating or cooling
the supply fan operates at the minimum speed setting while
providing ventilation according to occupancy setpoints.
Alternately, the supply fan can be setup to cycle off when
there is no demand for heating or cooling.
Single Zone VAV – Cooling
Cool — When there is a space cooling demand, DX
cooling will initialize and increase to satisfy space
temperature. The supply fan will continue to operate at a
low, fixed speed at low cooling capacities until the cooling
capacity requires additional airflow to keep compressor
operation optimal. The supply fan speed will increase as
the demand for cooling capacity increases. The minimum
supply fan speed is calculated by DX cooling capacity. As
the space requires additional cooling capacity, Space
Temperature Control will calculate a lower discharge air
temperature setpoint increasing DX cooling which in turn
increases the supply fan speed (to prevent coil frost).
Cooling capacity and supply fan speed both can increase
to 100%.
If the unit discharge air temperature reduces to the
Discharge Air Temperature Minimum Cool Limit setting or
DX cooling reaches 100% capacity, cooling capacity
increases will hold while the supply fan speed will continue
to increase to 100% or modulate to manage space comfort
cooling.
Cool Economizer — If the unit is configured for a
modulating outdoor air damper and conditions are suitable
for economizer cooling, the supply fan will operate at
minimum speed while the economizer damper modulates
between the Outdoor Air Damper Minimum Position (or
Flow) Setpoint and 100% to satisfy the discharge air
temperature setpoint. If the economizer damper reaches
100% open and additional cooling capacity is required, the
supply fan will then modulate between minimum speed and
100% to provide additional cooling to the space.
Cool Econ DX — Cool – Econ DX is
reported as the Unit sub-mode of operation when both
economizer and DX cooling are active. If actively
economizing, outdoor air damper is 100% and supply fan
speed reaches 100% then DX cooling will be added if the
unit is not satisfying space cooling requirements.
If DX cooling is active and economizer cooling enables, the
control will transition to increase economizer damper above
minimum position (or flow setpoint) to 100% to satisfy
space cooling while decreasing DX cooling. DX cooling will
steadily be removed as long as economizer cooling is able
to satisfy the cooling load. The supply fan operates to the
lowest speed possible during the transition.
Single Zone VAV – Heating
The supply fan operates at minimum speed (or will cycle
off) when the space has no heating demand. When space
temperature control calculates an increasing demand for
heat in the space, the calculated discharge air temperature
setpoint will increase. When heating capacity initiates, the
supply fan will operate at the required minimum speed for
Sequence of Operation