NOL Compact Modulating
Page 10
The volume of air required for combustion must
also be varied as the nozzle output varies, and this
is done by the air control damper operated by a
flexible steel cable connected to a lever system
bearing against the air control cam.
Once the oil cam has been adjusted as described
in the
commissioning
section of this handbook, the
profile of the air cam must be adjusted to give the
required combustion conditions. This is achieved
by turning the thumbscrews under the cam in or
out as the burner is inched through its firing range.
The air control damper is spring loaded open for
safety in the event of cable failure.
O
PERATION
When the boiler control calls for heat, the burner
modulating unit will travel to the high flame
position and interlock the control circuit. An air
pre purge will take place at this position for a pre
determined period, at the end of which the burner
sequence controller will stop until the modulating
unit has travelled to the low flame position and
interlocked the control circuit again. The sequence
control will now recommence its operational cycle
and the burner will light and remain at low flame
until the high flame release signal is given by the
sequence control.
Under the instruction of the modulating controller,
the modulating unit will now move to high flame
and remain at this position until the desired boiler
temperature/pressure is attained. From this stage,
the modulating controller will drive the burner
towards the low flame position, but, depending
on the temperature/pressure, will stop in any
intermediate position between low and high
flame.
C
OMMISSIONING
I
MPORTANT
- S
AFETY
It is essential that commissioning shall be
undertaken only by suitably qualified and
experienced personnel. In the case of NOL
Modulating burners, commissioning engineers
should be experienced in pressure jet oil burner
commissioning. Nu way can accept no
responsibility for consequential loss, damage or
personal injury which results from a failure to follow
the commissioning instructions provided or from
commissioning procedures being undertaken by
unqualified personnel.
E
MERGENCY
I
NSTRUCTIONS
NOL Modulating burners are designed and
constructed to meet current legislation. When used
in accordance with the instructions provided, NOL
Modulating burners are unlikely to produce a
hazardous condition. If, however such a condition
should arise in connection with the burner, the
appliance or of any instrument, machine or service
in the vicinity of the burner, the
OIL AND
ELECTRICITY SUPPLIES
SHALL BE ISOLATED
IMMEDIATELY
and they shall remain isolated until
the fault has been identified and rectified.
Inspection
Before commissioning is begun it is important to:
Check that the electrical wiring is complete
and complies with all applicable Codes and
Standards.
Ensure that the fuses are fitted and are of the
correct rating.
Check electrical earthing.
Verify that the oil supply system is correctly
designed and that the supply pipework is
correctly sized and free from leaks.
Ensure that all manual fuel isolation valves
are operable, fully closed and leak tight.
Make all personnel involved in the
commissioning aware of the location of the
emergency fuel and electricity isolation
points.
Check that fittings for bleed and pressure
testing are fitted.
Establish that the appliance is in an
appropriate and safe condition to be fired;
for example, that there is water in the boiler.
Set the appliance controls to call for heat.
Check the appliances ventilation and flueing
arrangements.
Ensure that any warning notices appropriate
to the commissioning procedure are in
position.
Ensure that all necessary tools and test
equipment are available and ready for use.
Essential items include temperature
measuring instruments for measuring flue gas
and appliance water temperatures, and a
means of analysing the flue products for
carbon dioxide (CO
2
), oxygen (O
2
), carbon
monoxide (CO) and smoke.
