Trane Symbio 700 Controller User Manual

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ACC-APG002A-EN
Outdoor Air Damper Control
Economizer Cooling
Symbio™ 700 supports a 0 to 100% economizer damper which requires a discharge air temperature
sensor to be installed for economizer cooling. There are four configurable economizer types: fixed dry
bulb, differential dry bulb, reference enthalpy, and comparative enthalpy. Each type, enable, and the
high limit disable criteria are defined as follows.
Table 4. Economizer types
Fixed Dry
Bulb
Enable
Outdoor Air Temperature < Economizer Outdoor Air Enable Setpoint – Economizer Dry Bulb
Enable Offset
Disable
Outdoor Air Temperature > Economizer Outdoor Air Enable Setpoint
Differential
Dry Bulb
Enable
Outdoor Air Temperature < (Return Air Temperature - Economizer Dry Bulb Enable Offset -
Economizer Dry Bulb Disable Return Air Offset)
Disable
Outdoor Air Temperature < (Return Air Temperature - Economizer Dry Bulb Disable Return Air
Offset)
Reference
Enthalpy
Enable
Outdoor Air Enthalpy < (Economizer Outdoor Air Enthalpy Enable Setpoint – Economizer Cooling
Reference Enthalpy Offset)
AND
Outdoor Air Temperature < (Economizer Outdoor Air Enable Setpoint – Economizer Dry Bulb
Enable Offset)
Disable
Outdoor Air Enthalpy > Economizer Outdoor Air Enthalpy Enable Setpoint
OR
Outdoor Air Temperature > Economizer Outdoor Air Enable Setpoint
Comparative
Enthalpy
Enable
Outdoor Air Enthalpy < (Return Air Enthalpy – Economizer Cooling Reference Enthalpy
Hysteresis Offset)
AND
Outdoor Air Temperature < (Economizer Outdoor Air Enable Setpoint - Economizer Dry Bulb
Enable Offset)
Disable
Outdoor Air Enthalpy > Return Air Enthalpy
OR
Outdoor Air Temperature > Economizer Outdoor Air Enable Setpoint
While the configuration parameters will be used to determine which method of economizer control will
be utilized, the table below describes the needed sensor data for each control method.
Table 5. Sensor data
Economizer Enable Method
Required Sensor Data
Comparative Enthalpy
Outdoor Air Temperature
Outdoor Air Humidity
Return Air Temperature
Return Air Humidity
Reference Enthalpy
Outdoor Air Temperature
Outdoor Air Humidity
Dry Bulb Outdoor Air Temperature
Differential Dry Bulb Outdoor Air Temperature

Trane Symbio 700 Controller Specifications

General

Brand	Trane
Model	Symbio 700 Controller
Category	Controller
Language	English