Adjustment Prior To Ignition; Servomotor; Burner Start-Up; Burner Ignition - Riello RS 25/M BLU Installation, Use And Maintenance Instructions

MIN GAS PRESSURE SWITCH
(A)
(C)

SERVOMOTOR

(D)
(E)
In the event of a burner lockout, more than two consecutive burner reset opera-
tions could cause damage to the installation. On the third lockout, contact the Af-
tersales Service.
If further lockouts or burner faults occur, interventions must only be made by
qualified, authorised personnel (as indicated in this manual, and in compliance
with the laws and regulations currently in force).
AIR PRESSURE SWITCH
D3855 (B)
ADJUSTMENTS PRIOR TO IGNITION
THE FIRST IGNITION MUST BE CARRIED
OUT BY QUALIFIED PERSONNEL WITH THE
RIGHT INSTRUMENTS.
The adjustment of the combustion head, air,
was described on page 8.
In addition, the following adjustments must also
be made:
- open manual valves up-line from the gas
- Adjust the minimum gas pressure switch to
- Adjust the air pressure switch to the start of the
D3854
- Purge the air from the gas line.
- Assemble a pressure gauge (C) on the gas
- Connect two lamps or testers to the two gas
Before starting up the burner, it is good practice
D3841
to adjust the gas train so that ignition takes
place in conditions of maximum safety, i.e. with
gas delivery at the minimum.
SERVOMOTOR (D)
The servomotor provides simultaneous adjust-
ment of the air damper, by means of the variable
profile cam and the gas butterfly valve.
The angle of rotation of the servomotor is equal
to the angle on the graduated sector controlling
the gas butterfly valve.
The servomotor rotates through 90° degrees in
24 seconds.
Do not alter the factory setting for the 4 cams;
simply check that they are set as indicated
below:
Cam I
Limits rotation toward maximum position. When
the burner is at max output, the gas butterfly
valve must be fully open: 90°.
Cam I I
Limits rotation toward the minimum position.
When the burner is shut down, the air damper
D7679 and gas butterfly valve must be closed: 0°.
Cam I I I
Adjusts the ignition position and the MIN output.
Cam I V

BURNER START-UP

Switch off the remote controls and place the
switch 1)(E) in position "MAN".
As soon as the burner starts, check the direction
of rotation of the fan blade, looking through the
flame inspection window 17)(A)p.4. Make sure
that the lamps or testers connected to the sole-
noids, or pilot lights on the solenoids them-
selves, indicate that no voltage is present. If
D3833
voltage is present, stop the burner immediately
and check the electrical connections.

BURNER IGNITION

Having completed the checks indicated in the
previous heading, ignition of the burner should
be achieved. If the motor starts but the flame
does not appear and the control box goes into
lockout, reset and wait for a new firing attempt. If
ignition is still not achieved, it may be that gas is
not reaching the combustion head within the
safety time period of 3 seconds. In this case,
increase gas ignition delivery. The arrival of gas
to the pipe coupling is shown by the pressure
gauge (C). Once ignition has taken place, pro-
ceed with global calibration operations.
10
ATTENTION
train.
the start of the scale (A).
scale (B).
Continue to purge the air (we recommend
using a plastic tube routed outside the build-
ing) until gas is smelt.
pressure socket of the pipe coupling.
The manometer readings are used to calcu-
late MAX. burner power using the tables on
page 6.
line solenoid valves VR and VS, to check the
exact moment at which voltage is supplied.
This operation is unnecessary if each of the
two solenoid valves is equipped with a pilot
light that signals voltage passing through.
: 90°
: 0°
: 15°
: Integral with cam III