Smeg SNL574GH - Manual (Page 13)

Instructions for the installer
33
6.3 Arrangement of burners on hob
Burners
1.
Auxiliary
2. Semirapid
3. Rapid
4. Rapid large
6. Ultra rapid
7. Double crown
8. Fish pan
10. Double crown
6.4 Lubrication of gas taps
After a while, the gas tap may become hard to turn or lock. If this
happens, it has to be cleaned inside and re-greased.
This must be done by a qualified technician.