The gas valve is a mechanism used for gas distribution. When there is a need for more gas in the burner, a message is sent from the electronic control to the gas valve, which opens and allows gas to flow through the valve in to the burner or the pilot assembly dependant on the type of appliance installed.
This part fits Ariston Microgenus 23 MFFI and Ariston Microgenus 27 MFFI