10/2016 - Art. Nr. 4200 1016 3901A
33
en
Start up
Setting the MB-DLE407 compact gas unit
Locking
screw
Sealed
screw
Initial load flow adjustment - rapid
stroke adjustment
• Twist off protective cap
5
and turn it
through 180° to use it as an
adjustment tool.
• Turn the adjustment spindle towards
the minus symbol, then turn it back
towards the plus symbol to the middle
position (approximately 3 half turns).
The initial gas flow is now set to
around half open.
• To achieve smooth start-up
characteristics, the initial gas flow
should be adapted to the pressure
characteristics of the heat generator.
Pressure controller setting
The adjusting screw has a path of 60
turns for adjusting the output pressure.
Three turns clockwise or anti-clockwise
increases or reduces pressure by 1
mbar respectively.
At commissioning:
• Turn the screw at least 20 turns
clockwise (+)
• The gas pressure downstream of the
regulator
pBr
should be:
12-15 mbar (can be measured at the
gas pressostat measuring nipple)
119.1
).
Setting the rated load
• Loosen the locking screw until the
rotary knob
6
becomes adjustable. Do
not loosen the sealed screw on the
opposite side.
• Reduce the main flow by turning knob
6
clockwise or increase it by turning it
anti-clockwise. The total path to adjust
from minimum to maximum flow is
approximately 4.5 turns.
• Retighten the locking screw following
the adjustment.
• Measure the gas pressure at
measuring point
119pBr
(for factory
setting, see page 31).
Optimising combustion values
Optimum combustion values can be
achieved by adjusting the position of the
baffle plate (dimension
Y
) if necessary.
Doing this can have an effect on starting
characteristics, pulsation and
combustion values. Any reduction in
scale value
Y
increases the CO
2
value.
However, starting characteristics
become harsher. Compensate for the
change in airflow if necessary by
adjusting the air flap position.
N.B.: Observe the minimum required
flue gas temperature specified by the
boiler manufacturer and the
requirements demanded of flue gas
ducts for avoiding condensation.
Checking the controllability
• Operate burner at rated load.
• Measure gas pressure at point
119
and
119pBr
.
• Close the ball valve upstream of the
compact unit slowly until the gas input
pressure at
119
falls to 20 daPa.
The gas outlet pressure at
119pBr
must not fall by more than 10 %.
Otherwise the setting is to be checked
and corrected.
The system must not be operated
when the controllability is
insufficient.
• Open the 90° manual shut-off valve.
