Flavel Curve Installation And Maintenance Instructions Manual page 13

Fig. 6
Note : Before breaking into the gas supply a tightness test should be carried
out to establish that the existing pipework is sound.
g) Before making the final gas connection, thoroughly purge the gas
supply pipework to remove all foreign matter, otherwise serious
damage may be caused to the gas control valve on the fire.
Spigot
Fire Opening
460mm
C/L
13
Gas Supply
Restrictor / PTP
Elbow
128mm
Closure Plate