Commissioning Screen - Trane Symbio 210 Installation, Operation And Maintenance Manual

Controller Points and Parameters
Discharge Air Reset Limits
The following parameters are used for Single Duct Units that are equipped with either modulating hot
water reheat or SCR electric heat, which allows variable airflow when reheat is activated (for example,
"dual maximums" control sequence).
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Commissioning Screen

Actions
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Minimum Heat when local heat is on. This entry must be less than or equal to the entry for Airflow
Setpoint Maximum Heat.
Airflow Setpoint Reset Minimum Local Heat: The minimum position/flow when local heat (either
modulating hot water or SCR electric) is on. This entry must be less than or equal to the entry for
Airflow Setpoint Reset Maximum Local Heat. When reheat is initially activated the air valve opens
to, and remains at, this minimum position/flow setpoint, while reheat capacity is modulated to
maintain the space temperature at the active heating setpoint. Once reheat capacity has increased
to the point that the discharge air temperature reaches the Discharge Air Temperature Design
Setpoint, the controller will begin to increase airflow above this minimum setpoint.
Airflow Setpoint Reset Maximum Local Heat: The maximum position/flow when local heat (either
modulating hot water or SCR electric) is on. This entry must be greater than or equal to the entry for
Airflow Setpoint Reset Minimum Local Heat. Once reheat capacity has increased to the point that
the discharge air temperature has reached the Discharge Air Temperature Design Setpoint, the
controller will begin to increase airflow above Airflow Setpoint Reset Minimum Local Heat. If the air
valve reaches this maximum setpoint, reheat capacity is allowed to increase further, raising the
discharge air temperature, while the air valve remains at Airflow Setpoint Reset Maximum Local
Heat.
Discharge Air Temperature Reset Maximum: This is the maximum discharge air temperature
allowed when local heat (either modulating hot water or SCR electric) is on. Once the controller has
increased airflow to Airflow Setpoint Reset Maximum Local Heat, reheat capacity is allowed to
increase further, raising the discharge air temperature, but not above this maximum limit.
Discharge Air Temperature Design Setpoint: When local heat (either modulating hot water or
SCR electric) is initially activated, the air valve will maintain position/flow at Airflow Setpoint Reset
Minimum Local Heat and begin increasing reheat capacity. Once reheat capacity has increased to
the point that the discharge air temperature has reached this design setpoint, the controller will
begin to modulate airflow between Airflow Setpoint Reset Minimum Local Heat and Airflow Setpoint
Reset Maximum Local Heat, while reheat capacity is modulated to maintain the discharge air
temperature at this design setpoint.
Note: When the parameters on this tab are used, leave Airflow Setpoint Minimum Local Heat (found
in the Flow Setpoints Setup section) at the factory configured value. If there is a fault with the
discharge air temperature sensor, the controller reverts to Airflow Setpoint Minimum Local
Heat when local heat is on.
Zero Air and Water Valve Position (Start Button): The calibration sequence enables the controller
to calibrate the air valve position and the water valve position, as well as calibrate the flow sensor.
Auto-commissioning (Start Button): The controller auto-commissioning test sequence validates
both the proper operation of all outputs and the capability to measure all inputs. The purpose of the
test sequence is to minimize the labor required to commission the unit in the field.
The auto-commissioning test does not require a flow sensor or a discharge or supply air
temperature sensor. If there is no flow sensor, the controller runs in pressure-dependent mode.
A temperature sensor in the discharge air stream is required for testing of the fan and the reheat.
The fan and the reheat are not tested if the discharge air temperature sensor is not present. The
fan is not tested if there is no fan. Local reheat is tested, if it is present. Remote reheat is not
tested.
The sequence starts on receipt of an auto-commission command from the Tracer TU service
tool start button or the Tracer SC+. The auto-commission command contains a time/date stamp.
No 3rd party tool can start the auto-commissioning sequence. The user then chooses to
commission all VAV boxes or one VAV box. The results of auto-commissioning are contained in
a structured network variable called reported auto commissioning report. The controller places
BAS-SVX091A-EN