FloAire Demand Control Ventilation System - Manual (Page 15)

A0023662
May 2014 Rev.5
15
Functionality
Fan Control
The control panel controls fans through VFDs. They are used to adjust the speed of 3 phase motors and
frequency is proportional to airflow. There is one VFD for each fan in the system.
Preparation Time Mode
1. This option is enabled by default from the factory.
It can be disabled under Configuration → Factory options.
2. Preparation Time Mode is available for morning operation when appliances are off or when very light
food preparation is performed. Dedicated make-up air will be locked out only allowing the use of
transfer air during this mode. Exhaust fan(s) will run at low CFM while maintaining a balanced kitchen
pressure.
3. Preparation Time mode can be initiated by different means:

By pressing the FANS button on the HMI

When the duct temperature exceeds Prep activation point =Room Temperature + Temp Offset/2
(Factory Default: 7.5 °F).
4. The fans will go back to running in modulation mode if the PREP OFF button is pressed or if the
temperature sensors in the duct measure a temperature above the activation Temperature value.
5. The speed of the exhaust fan(s) in Preparation Time is calculated automatically and is equal to
the speed that will produce the same amount of CFM than the Transfer CFM when the fans are
running in full speed in normal operation. If there is no dedicated supply fan in the system, the
exhaust fans will run at the set High Frequency divided by 4 (typically 15 Hz).
NOTE: If the calculated value falls below the set minimum frequency, then the value will be adjusted
to the lowest allowable frequency.
Hood Lights
1. A control panel can have 1 HMI light switch but potentially controls multiple light circuits. Each
light circuit can feed with a maximum of 1400W. If more than 1400 watts of lights are needed,
additional 15 amp circuits can be brought to the panel. Panel specific lighting limitations are
indicated on the installation schematic.
2. Hood lights can be controlled manually through the LIGHTS button on the HMI. They will also be
automatically turned ON or OFF when the fans assigned to that same fan zone turn ON or OFF.
Manual light switch command on the HMI always takes priority.
Electric Gas Valve Reset
If the Gas Valve option is turned ON or the system is equipped with CORE Fire Protection, an additional
button (GAS RESET/GAS ON) is displayed on the HMI to allow the user to reset or re-energize an electric
gas valve connected to the panel. The gas valve is de-energized at initial startup, when the Fire System is
triggered or in other conditions as well.
Refer to paragraph (h) under Configuration section to turn this option ON or OFF.
High Temperature Automatic Appliance Shutdown
When any of the duct temperature sensors reads a temperature above the Appliance Shutdown
Temperature threshold settings (Factory Default: 250 Degrees °F), any electric gas valve wired to the
panel will shut down and the shunt trip output of the panel will activate. This is intended to prevent
potential fires. The activation threshold set point can be adjusted under Configuration/Fire Options.
Make-Up Air Interlock
When the dedicated supply fan is a Tempered Make-up Air unit, the blower inside the supply unit can be
interlock so that it will not run unless the safety controls (Freezestat, CO sensor, Smoke Detector etc.)
inside the supply fan are armed and until the internal motorized damper has reached its end limit switch.