The application function for fan coil applications lowers the relative humidity by overriding the coiling coil valve position and setting the fan to the correct speed for dehumidification. The integrated PID controller compares relative room humidity with the setpoint corresponding to the active room operating mode. The PID controller operating mode is set to 2-point (off/dehumidification) to activate maximum output if the temperature for dehumidification must be lowered.

The cooling coils are controlled with the command to dehumidify, while also coordinating that state with the controller that the cooling coils are ready for dehumidification.

A humidity sensor in the room is required for dehumidification control. The application automatically enables dehumidification control as soon as an humidity sensor and cooling coils are configured.

Setpoints

Dehumidification setpoints can be configured separately for each room operating mode.

Description

Name

Default value

Relative room humidity setpoint for comfort

SpHuRelRCmf

60 % r.h.

Relative room humidity setpoint for pre-comfort

SpHuRelRPcf

60 % r.h.

Relative room humidity setpoint for economy

SpHuRelREco

70 % r.h.

Relative room humidity setpoint for protection

SpHuRelRPrt

70 % r.h.