Riello DB 4 SM BLU Installation, Use And Maintenance Instructions page 31

4.2 Wiring diagrams
All the installation, maintenance and disassembly operations must be carried out with the electricity supply disconnected.
DANGER
The installation of the burner must be carried out by qualified personnel, as indicated in this manual and in compliance with the
standards and regulations of the laws in force.
WARNING
Fig. 13
Burner terminal strip
MB
Air pressure switch
PA
PGM Maximum gas pressure switch
Servomotor
SM
4
CHAPTER Fuel supply
Ionisation probe
SO
Ignition transformer
TA
Burner earth
TB
D7904
11