OK you lot let me explain about this “Gas Meter” set up you have in the picture.
The Inlet from the street gas main is on the laft hand side and the device fitted above the isolating valve is the Gas Companies governor (pressure reducing device) which breaks down the gas supply pressure from that which is supplied in the street mains to a safe reticulation pressure to supply into a residential/commercial property. Once the outlet pipe (on the right) is connected to appliances inside each of them will have a smaller governor fitted to further reduce the pressure to that which the appliance manufacturer has specified for correct operation.
Simple stuff huh?
Selgas Services Ltd
Craftsman Gasfitters, Plumbers, Electrical Service Technicians