Riello DB 16 SM C01 TC A0 FS1 T250 Installation, Use And Maintenance Instructions page 34

5.3 Servomotor adjustment
1 - 4 : Limit switch cam (max. air damper opening)
2 : Limit switch cam (air damper closed)
3 - 5 : Minimum delivery (and ignition) position cam
6 : Positioning reading indicator
7 : Servomotor release
The servomotor contemporarily regulates, by transmission, air delivery
and pressure and delivery of the fuel being used.
It is fitted with a number of adjustable cams that action the same
number of selector switches.
Cam pos.1: limits maximum opening of the servomotor.
Cam pos.2: limits servomotor limit switch in the 0° position.
When the burner is off, the air damper is completely
closed.
Cam pos.3: fixes the minimum modulation position.
It is set in the factory at approx. 20° (just one type of fuel).
Cam pos.4: limits maximum opening of the servomotor (for mixed burners working with gas).
Cam pos.5: limits minimum delivery. It is set in the factory at approx. 20° (for mixed burners working with gas).
Cam rest: available.
Important: the position of 130° must not be exceeded for limit switches (cam 1 - 4).
5.4 Pressure switches adjustment
As the reference pressure levels cannot yet be established, before beginning setting operations, the following must be carried out
(with the burner turned off):
• open the manual valves upstream from the gas train;
• adjust the minimum gas pressure switch (Fig. 19) on the gas train, at the start of the scale;
• adjust the maximum gas pressure switch (Fig. 20), on the butterfly valve, at the end of the scale;
• adjust the air pressure switch (Fig. 21) on the burner air box, at the start of the scale.
Minimum gas pressure switch
D2214
Fig. 19
14
CHAPTER
Maximum gas pressure switch
D2213
Fig. 20
5
Preparation for start up
Air pressure switch
D2215
Fig. 21
D1500
Fig. 18