Gira hygrostat

The Gira hygrostat detects a room’s humidity and temperature using internal sensors. If the humidity exceeds the setpoint on the rotary knob, the Gira hygrostat switches on an externally connected fan to dehumidify the room. In the process, the device treats the setpoint dynamically, i.e. it takes account, within certain limits, of the fact that warmer air can absorb more moisture than colder air. For example, if the Gira hygrostat measures a higher room temperature than the reference temperature of 21°C, it permits a correspondingly higher degree of humidity. This avoids unnecessary ventilation and saves energy.

A runtime monitoring function prevents excessively long dehumidification when the ambient air is too humid, e.g. when there is a likelihood of thunderstorms. To prevent unrestricted operation of the connected fan, the Gira hygrostat changes to standby mode after approx. 1 hour. Then the fan is switched off for approximately 4 hours. If the humidity is still too high after 4 hours, the fan is switched on again. This operating mode is signalled with a red LED and can be manually adjusted using the operating button.

The Gira hygrostat can be set to fixed setpoint control on the back of the device so that the humidity setpoint isn’t changed without authorisation, for example in rented apartments or public buildings. The setpoint is then permanently set to 60% relative humidity, regardless of the position of the rotary knob on the front of the device.

For optimum operation, the installation spot should be at a height of approx. 1.5 m, with no direct exposure to sunlight, draught air or heat radiated from electrical devices, and it should not be directly in the radiation area of heaters. It is also advisory not to install the Gira hygrostat in a unit with electrical devices that produce heat (e.g. dimmers). A moisture-absorbing surface (e.g. plasterboard) can affect the control behaviour, therefore installation on a surface that does not absorb moisture is recommended, such as tiles. In bathrooms spacing must be observed in accordance with DIN VDE 0100-701.