Adjustment Before First Firing (Gas Operation); Burner Starting; Burner Firing - Riello RLS 250/M MZ Installation, Use And Maintenance Instructions

MIN GAS PRESSURE SWITCH
D3855
(A)
(D)
(E)
MAX GAS PRESSURE SWITCH
D3856
(B)
1 2
AIR PRESSURE SWITCH
D3854
(C)
D3916
D791
14
ADJUSTMENTS BEFORE FIRST FIRING
(gas operation)
Adjustment of the combustion head has been
illustrated on page 8.
In addition, the following adjustments must also
be made:
- Open manual valves up-line from the gas
train.
- Adjust the minimum gas pressure switch to
the start of the scale (A).
- Adjust the maximum gas pressure switch to
the start of the scale (B).
- Adjust the air pressure switch to the zero
position of the scale (C).
- Purge the air from the gas line.
Continue to purge the air (we recommend
using a plastic tube routed outside the buil-
ding) until gas is smelt.
- Fit a U-type manometer (D) to the gas pres-
sure test point on the sleeve.
The manometer readings are used to calcu-
late the 2nd MAX. burner power using the
table (A)p.13.
- Connect two lamps or testers to the two gas
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.
Before starting up the burner it is good practice
to adjust the gas train so that ignition takes
place in conditions of maximum safety, i.e. with
gas delivery at the minimum.
BURNER STARTING (gas operation)
N.B.: It is advisable to first set the burner for
operating on oil and then for gas.
WARNING
Execute the fuel exchange when the burner
is off.
Close thermostats/pressure switches and set
switch 1)(E) to "MAN" position.
As soon as the burner starts check the direction
of rotation of the fan blade, looking through the
flame inspection window 26)(A)p.4.
Make sure that the lamps or testers connected
to the solenoids, or pilot lights on the solenoids
themselves, indicate that no voltage is present.
If voltage is present, then immediately stop the
burner and check electrical connections.
BURNER FIRING (gas operation)
Having completed the checks indicated in the
previous heading, the burner should fire. If the
motor starts but the flame does not appear and
the control box goes into lock-out, 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 firing delivery.
The arrival of gas at the sleeve is indicated by
the U-type manometer (D).
Once the burner has fired, now proceed with
global calibration operations.