Control the Environment
The System controls the room environment by engaging one of four modes: Cool, Dehumidify, Reheat, or Humidify. These modes may work differently depending on the options and equipment installed in your Modules.
The environmental controls are set when your System is installed. Changing settings described in this section after the system has been commissioned may result in improper operation.
How the modes work
Cool. When the cool mode uses a Chilled Water coil, the output is determined by the difference between the setpoint and the measured air temperature (control temperature) of each of the Modules in the System (if more than one Module is present). The control temperature can be the average return sensor value, the average remote sensor value, or the maximum remote sensor value, depending on the System settings (Path: Main > Setup > System > System Setup > System Config > Sensor Setup)
See “Sensor setup” on page 9 to choose the source of the temperature value which the Module uses to calculate demand.
The Proportional plus Integral plus Derivative (PID) control loop calculates the output as demand increases and opens the valve controlling the flow of coolant into the coil. The PID adjusts the output as required to maintain the temperature at the setpoint.
See “PID controls” on page 23 for a description of the PID controls and instructions on tuning the fluid coil PID loop.
Reheat (Electric SCR and Modulating Hot Water). The SCR
See “PID controls” on page 23 for a description of the PID controls and instructions on tuning the reheat PID loop.
Reheat (Hot Gas, Steam, Hot Water On/Off). The output of the hot gas, steam, and hot water on/off reheat options is determined by the difference between the setpoint and control temperature of the Module. When the control temperature at the Module reaches the setpoint minus the deadband, the reheat mode activates until the control temperature rises to the setpoint.
See “Deadbands” on page 22 for acceptable reheat deadband values.
20 | NetworkAIR IR Operation, Maintenance, and Troubleshooting |
