Riello RLS 250/M, Installation, Use And Maintenance Instructions

20034293

30 

GB

Start-up, calibration and operation of the burner

Key Fig. 37
1

Servomotor

2

Servomotor 1) - Cam 4): engaged

3

Servomotor 1) - Cam 4): disengaged

4

Adjustable profile cam

5

Cam starting profile adjustment screws

6

Adjustment fixing screws

7

Cam end profile adjustment screws

8

Graduated sector for gas butterfly valve

9

Index for graduated sector 8

10 Key for cam III adjustment 

6.7.3

MIN burner output

Min output must be selected within the firing rate range shown on
pag. 11.
Press button 2)(Fig. 36 at page 29) “output reduction” until the
servomotor has closed the air gate valve and the gas butterflu
valve to 30° (factory set adjustment).

Adjusting gas delivery

Measure the delivery of gas from the gas meter.
–

If this value is to be reduced, decrease the angle of cam III
(Fig. 38) slightly by proceeding a little at a time until the angle
is changed from 30° to 28° - 26°....

–

If it has to be increased press the button “output increase”
2)(Fig. 36 at page 29) (i.e. open the gas butterfly valve by 10-
15°), increase the cam III angle (Fig. 38) with small succes-
sive movements, i.e. take it from angle 30° to 32° - 34°....
Then press the button “output decrease” until the servomotor
is taken to the minimum opening position and measure the
gas delivery.

In order to adjust cam III, especially for fine movements, the key
10)(Fig. 38), held by a magnet under the servomotor, can be
used.

Adjustment of air delivery

Progressively adjust the starting profile of cam 4)(Fig. 37) by turn-
ing the screws 5). 
It is preferable not to turn the first screw since this is used to set
the air gate valve to its fully-closed position. 

6.7.4

Intermediate outputs

Adjustment of gas delivery

No adjustment of gas delivery is required.

Adjustment of air delivery

Press the key 2)(Fig. 36 at page 29) “output increase” a little so
that the servomotor turns by about 15°.
Adjust the screws until optimal combustion is obtained. Proceed
in the same way with the other screws.



Switch off the burner using switch 1)(Fig. 36 at page 29), at
OFF position;



disengage the cam 4)(Fig. 37) from the servomotor, by
pressing the button 3)(Fig. 38) and moving it to the right, and
check more than once that the movement is soft and
smooth, and does not grip, by rotating the cam 4) forward
and backward by hand.



Engage the cam 4) to the servomotor again by moving the
button 2)(Fig. 38) to the left.



Finally fix the adjustment by turning the screws 6)(Fig. 37).

NOTE:

Once you have finished adjusting outputs MAX - MIN - INTER-
MEDIATE, check ignition once again: noise emission at this
stage must be identical to the following stage of operation.
If you notice any sign of pulsations, reduce the ignition stage de-
livery.

WARNING

The servomotor follows the adjustment of cam III
only when the cam angle is reduced. If it is neces-
sary to increase the cam angle, first increase the
servomotor angle with the key “output increase”,
then increase the cam III angle, and finally bring
the servomotor back to the MIN output position
with the key ”output decrease”.

 Fig. 37

D1710

WARNING

Take care that the cam profile variation is progres-
sive.

WARNING

As far as is possible, try not to move those screws
at the ends of the cam that were previously adjust-
ed for the opening of the air gate to MAX and MIN
output.

 Fig. 38

D3924

10

2

3