RHR-DPPressure gauge for RHR-CF

The Residential Heat Recovery Couterflow units RHR-CF are high efficiency ventilation units with heat recovery and are designed for residential ambiences.

The calibration system of standard units consists in a manual balancing operation performed by the responsible technician, using a digital pressure gauge. After the first calibration, the unit control board is programmed to maintain the nominal and partial flow rate close to the desired value through fan speed control (indirect flow rate control method).

Alternatively, an advanced control strategy is envisaged, enabling automatic flow rate calibration and maintaining it thanks to the action of differential pressure switches connected to the suction nozzles of the centrifugal fans. The pressure drop measured by this type of sensors is directly related to the flow rate of the fans, so that it can be considered as a direct flow rate measurement. If the units are equipped with accessory transmitters, the main control board detects the actual system flow rates at all times, making it react automatically to maintain the desired actual values.