Temperature and Humidity Controllers

A temperature or humidity controller reads the grow room air and drives the extractor accordingly. As soon as the set threshold is crossed, ventilation speeds up; it slows again once the reading returns to range. The climate holds itself, without daily intervention.

Threshold or hysteresis control

Threshold control is binary: below the setpoint the fan runs at minimum, above it jumps to maximum. Simple and effective for holding a ceiling temperature, but it produces abrupt transitions. Hysteresis control introduces a temperature band across which speed rises progressively — a steadier climate and less strain on the motor.

Temperature, humidity, or both

A thermostat acts on heat, a humidistat on relative humidity. The two are linked: ventilating to bring temperature down also draws in outside air, whose moisture changes the room. Units handling both prevent the two setpoints from working against each other.

The sensor is the weak point of the install

A probe placed too close to a lamp, or in the extractor’s direct airflow, measures something other than the air the plants breathe. Site it at canopy height, in the shade, away from the outlet.