Viconics VT7607 Installation Manual - Manual (Page 16)

16 | PIR Ready VT76x7 Series-Installation Guide
50% RH and the dehumidification setpoint is changed from 70% RH to 45% RH, the
humidification setpoint will be modified to 45% RH by the Terminal Equipment Controller.
Humidification process
Humidification process will only be allowed when the Terminal Equipment Controller is in
heating mode (System Mode = Heat or System Mode = Auto and effective mode at the
Terminal Equipment Controller is heat). If there is a humidification demand and the fan is
OFF, the fan is first turned ON and the humidifier output is then activated.
Other than having the RH setpoint, the following events can stop the humidification
process at any time: RH sensor is out of range, System Mode is switched to Off or Cool
and the System Mode = Auto but the room’s effective mode changes from Heat to Cool
Dehumidification process
If (Dhu LCK) Dehumidification Lockout Functions is set to On (Enabled):
Dehumidification process will only be allowed when the Terminal Equipment Controller is
in cooling mode (System Mode = Cool or System Mode = Auto and effective mode at the
Terminal Equipment Controller is cool). If there is a dehumidification demand and the fan
is OFF, the fan is first turned ON and the dehumidification output is then activated.
Other than having reach the dehumidification setpoint, the following events can stop the
dehumidification process at any time:

RH sensor is out of range

System Mode is switched to Off, Heat or System Mode = Auto and effective
mode at the Terminal Equipment Controller is Heat

The room temp drops below the cooling setpoint minus the deadband value

The Outside air temp is below the Dhu OALK parameter
If (Dhu LCK) Dehumidification Lockout Functions is set to Off (Disabled):
Other than having reach the dehumidification setpoint, the following events can stop the
dehumidification process at any time:

RH sensor is out of range

System Mode is switched to Off

The Outside air temp is below the Dhu OALK parameter
Dehumidification process is allowed when the Terminal Equipment Controller operates in
all system modes except Off. If there is a dehumidification demand. If the fan is OFF, the
fan is first turned ON and the dehumidification output is then activated.
There is NO active temperature lockout protection in this mode. If the dehumidification
process causes the room temperature to rise or fall, the Terminal Equipment Controller
will react by either activating the cooling or heating outputs based on its current system
mode settings.