Adjustment Prior To Firing; Servomotor; Burner Start-Up; Burner Firing - Riello RS 34 MZ Installation, Use And Maintenance Instructions

MIN GAS PRESSURE SWITCH
(A)
(C)

SERVOMOTOR

(D)
Burner off
Burner on
(E)
AIR PRESSURE SWITCH
D3855
(B)
1 2
1st stage
2nd stage
ADJUSTMENTS PRIOR TO FIRING
THE FIRST FIRING MUST BE CARRIED OUT
BY QUALIFIED PERSONNEL WITH THE
RIGHT INSTRUMENTS.
The adjustment of the combustion head, air,
was described on page 9.
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 zero posi-
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
to adjust the gas train so that firing takes place
in conditions of maximum safety, i.e. with gas
D3841
delivery at the minimum.
SERVOMOTOR (D)
The servomotor provides simultaneous adjust-
ment of the air gate valve, by means of the vari-
able 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 12 seconds.
Do not alter the factory setting for the 4 cams;
simply check that they are set as indicated
below:
Cam St2
Limits rotation toward maximum position. When
the burner is in 2nd stage operation the gas but-
terfly valve must be fully open: 90°.
Cam St0
Limits rotation toward the minimum position.
When the burner is shut down the air gate valve
and the gas butterfly valve must be closed: 0°.
Cam St1
Adjusts the ignition position and the output in 1st
stage operation.
D517
Cam MV
Not used.

BURNER START-UP

Close the remote controls and set:
• switch 1)(E) to "Burner ON" position
• switch 2)(E) to "1st STAGE" position.
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 solenoids, or pilot lights on the solenoids
D469 themselves, indicate that no voltage is present.
If voltage is present, then immediately stop the
burner and check electrical connections.

BURNER FIRING

Having completed the checks indicated in the
previous heading, the burner should ignite. 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 firing 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 delivery
during firing. The arrival of gas at the pipe cou-
pling is indicated by the U-type manometer (C).
Once the burner has fired, now proceed with
global calibration operations.
10
ATTENTION
!
train.
the start of the scale (A).
tion of the 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°