The flow switch acts as a safety instrument. It is a switch with an in-built sensor that sits in the pipework for both the DHW and CH systems. When the pump is switched on, the flow switches senses this movement and feeds the information back to the PCB,

Brand Name	Ferroli
Colour	N/A
Material	N/A
Manufacturer Model No	39821530
Wear Type	N/A
Type	Flow Sensor
Certifications Met	N/A
Country of Origin	N/A
Protects From	N/A
Waterproof	N/A
Number of Pockets	N/A
Waist Size	aa85cj11gzERP
Rating	Not Applicable
Supplier Part Number	39821530