06/2004 - Art.Nr. 13 011 288C
48
Start up
Cycle test
Firing
Safety unit settings and checks
Burner power
(KW)
Burner head gas pressure
G20
G31
Air flap
position
Y10
(graduations)
Burner head
air pressure
pL
(daPa)
Dimension
Y
(mm)
pBr
(daPa)
(daPa)
NC9
GX207/8
1/2
pG1
pG
pG1
pG
1
2
1
2
45/60
55/72
55/84
34
42
43
58
72
93
47
63
62
72
103
132
2
6
6
8
13
18
38
27
28
38
43
50
15
25
30
Cycle test
·
Open and immediately reclose the
ball valve.
·
Switch the burner on.
·
Close the regulation circuit.
·
Unlock the safety unit and check
that it is working correctly.
The program sequence should be as
follows:
–
controlled preventilation time 20 sec.
(total preventilation time can exceed
20 sec.),
–
electrode ignition 3 seconds,
–
the valves open,
–
the valves close no more than
3 seconds after opening,
–
burner stops due to either lack of
gas pressure or control and safety
unit lockout due to flame
disappearance.
If unsure, repeat above test.
Firing is only possible after this
essential test of the ignition cycle has
been carried out.
Firing
Warning: the unit may be fired when all
the requirements listed in the previous
sections have been met.
·
Connect a microammeter scale
0-100µA DC in place of the
ionization bridge
B1
(check polarity).
·
Open the ball valve.
·
Close the 1
st
stage thermostat
circuit.
·
Unlock the safety unit.
The burner will operate.
·
Close the 2
d
stage thermostat circuit.
·
Perform a combustion test (CO -
CO
2
), as soon as the flame appears.
·
Check the ionization current (value
between 8 and 20µA).
·
Measure and compare (table):
– gas flow at the meter,
– gas pressure at point
pBr
and at
point
119 upstream
,
– air pressure at point
pL
.
·
If necessary, adjust:
– gas pressure using plug
C
of the
valve.
– air pressure using cam
V
of
servomotor.
·
Fine-adjust setting (dimension
Y
) and
the fire-rate changes (up and down)
using plastic stopper
B
of the valve.
·
Check combustion parameters.
The manufacturer’s recommendations
concerning: flue gas temperatures
(boiler) and CO
2
(burner) should be
followed in order to obtain the required
level of performance.
·
Return to 1
st
stage. Same procedure
as above, but use crown
D
of the
valve to set gas pressure and on
servomotor cam
IV
to obtain air
pressure.
·
With the burner working, and using
a foam designed for this purpose,
check for leaks in the valve
assembly connections.
No leaks should be observed.
Should analysis of the combustion tests
reveal that the CO value is too high,
modify it using the following diagrams:
1
Standard,
2
Modified
·
Fit the two distance pieces
C
(stored
on the plate) between turbulator
A
and diffusor
D
.
Safety unit settings and checks
Gas pressure switch.
·
Remove the cover to gain access to
the adjust screw.
·
Connect a pressure gauge to
pressure take-off
119 upstream
.
·
Read the actual supply pressure.
·
Switch the burner on.
·
Slowly close the ball valve.
Once the theoretical minimum pressure
(see table) is reached:
·
Determine the cut-off point by
turning screw
E
clockwise (
+
).
The burner should stop due to
insufficient gas pressure.
·
Turn the screw anticlockwise (
–
) one
turn (corresponds to 15 to 25daPa).
·
Check the setting by repeating the
test. Pressure switch is set.
m
Air pressure switch
·
Remove the terminal cover.
·
Connect a pressure gauge to the
+
pressure take-off.
·
Reopen the ball valve.
When the burner has been refired,
slowly turn screw
V
clockwise
(+
).
Determine and measure the cut-off
point (safety lockout).
·
Turner screw
V
anticlockwise (
–
)
one turn to set the required value
(differential 10-20daPa).
·
Restart the burner.
·
Gradually close off the burner air
intake.
·
Check that the CO value remains
below 1,000ppm prior to safety
lockout.
If not, increase the air pressure switch
setting and restart the test.
·
Disconnect the gas measurement
instruments.
·
Reclose the pressure take-offs.
·
Restart the burner.
·
Check for leaks downstream from
the valve assembly and between
flange and burner front.
·
Simultaneously disconnect both
microammeter cables.
The burner should immediately lock out
to safety.
·
Put the ionization bridge back in its
place.
·
Put the covers back in their places.
·
Restart the burner.
·
Check the combustion parameters
under actual service conditions
(doors closed, etc.) and test the
various connections for gas leaks.
·
Record results in the relevant
documents.
·
Set the burner to automatic mode.
·
Convey the required information for
proper operation.
Summary of Contents for NC9 GX207/8
Page 26: ...06 2004 Art Nr 13 011 288C 26 ...
Page 52: ...06 2004 Art Nr 13 011 288C 52 ...
Page 59: ...59 06 2004 Art Nr 13 011 288C ...