Riello RS 34/1 MZ, Installation, Use And Maintenance Manual

Page: 15 / 48

13
Note
Once you have finished adjusting maximum out-
put, check firing once again: noise emission at
this stage must be identical to the following
stage of operation. If you notice any sign of pul-
sations, reduce the firing stage delivery.
2 - AIR PRESSURE SWITCH (A)
Adjust the air pressure switch after having per-
formed all other burner adjustments with the air
pressure switch set to the start of the scale (A).
With the burner working insert a combustion
analyser in the stack, slowly close the suction
inlet of the fan (for example, with cardboard)
until the CO value does not exceed 100 ppm.
Then slowly turn the appropriate knob clockwise
until the burner reaches the lockout position.
Check the indication of the arrow pointing
upwards on the graduated scale (A). Turn the
knob clockwise again, until the value shown on
the graduated scale corresponds with the arrow
pointing downwards (A), and so recovering the
hysteresis of the pressure switch (shown by the
white mark on a blue background, between the
two arrows).
Now check the correct start-up of the burner.
If the burner locks out again, turn the knob anti-
clockwise a little bit more.
3 - MINIMUM GAS PRESSURE SWITCH (B)
With the burner operating, increase adjustment
pressure by slowly turning the relative knob
clockwise until the burner locks out.
Then turn the knob anti-clockwise by 5mbar and
repeat burner starting to ensure it is uniform.
If the burner locks out again, turn the knob anti-
clockwise again by 1mbar.
FLAME PRESENCE CHECK (C)
The burner is fitted with an ionisation system
which ensures that a flame is present. The mini-
mum current necessary for the control box oper-
ation is 5

A. The burner supplies a
significantly higher current value, so that no
check is usually needed. However, if it is neces-
sary to measure the ionisation current, discon-
nect the plug-socket 23)(A)p.4 on the ionisation
probe cable and insert a direct current microam-
perometer with a base scale of 100
μ
A. Care-
fully check polarities.
(A)
(C)
AIR PRESSURE SWITCH 4)(A)p. 4
MINIMUM GAS PRESSURE SWITCH
(B)
RMG
10
D3843
µA
D3855
D3951