Figure 7.4.8 Throttle Adjustment; Figure 7.4.11 Gas Valve Offset Adjustments; Table 7.1 Flue Gas Analysis Co2 Readings - Hamworthy MILBORNE381 Series Design Installation, Commissioning And Operating Instructions

8. The gas valve throttle setting can now be
regulated.
This is a based on the flue gas combustion analysis
rather than a fixed pressure. Check the CO
in accordance with table 7.1. If the CO
incorrect then adjustment must be made by
adjusting the gas valve throttle screw. Turning the
throttle screw anticlockwise increases the CO
value. Turning the throttle clockwise decreases the
CO value. See fig 7.4.8.
2
Note: To increase the gas flow turn the throttle
screw anti clockwise, to decrease the gas flow
turn the throttle screw clockwise.
Fig 7.4.8 - Throttle Adjustment
9. Allow the boiler to stabilise at maximum power
and if necessary readjust the gas flow rate.
10. Reduce the boiler power to minimum by
pressing switch S5 on the control panel.
The first digit of the display will indicate the fan
speed. L = minimum speed.
11. The minimum gas rate can now be set. This
again is based on the flue gas analysis rather than a
fixed pressure. Check the CO
with table 7.1. If the CO
adjustment must be made by adjusting the gas
valve offset adjustment screw. See figure 7.4.11.
Turning the offset screw anticlockwise decreases
the gas flow and decreases the CO
the offset clockwise increases the gas flow and
increases the CO value. See fig 7.4.11.
2
Note: To increase the gas flow turn the offset
screw clockwise, to decrease the gas flow turn
the offset screw anti-clockwise.
HAMWORTHY HEATING LTD
values
2
values are
2
values in accordance
2
values are incorrect then
2
value. Turning
2
2
Fig 7.4.11 - Gas Valve Offset Adjustment
12. Ensure that the combustion settings are still
correct at maximum output and if necessary repeat
steps 7 to 12 until the settings are correct.
Table 7.1: Flue Gas Analysis CO
Gas
Natural Gas
(model 381 & 501)
L.P.G.
(model 381)
L.P.G.
(model 501)
13. The individual
commissioned. If there are further modules to be
commissioned
module off using the external thermostatic controls
or time clock to ensure correct shutdown. Further
modules may now be commissioned individually by
following procedure detailed and used for the first
module.
14. Once all modules have been commissioned
switch all modules to the 'on' position and take a
dynamic gas inlet pressure test reading to ensure
that the gas supply is sufficient for full operating load
conditions. This should be taken at all boiler
modules to ensure the supply is satisfactory at all
boilers.
25
MILBORNE
Readings
2
Maximum
CO 9.2 - 9.4% CO
2
CO - (80 - 100ppm)
CO 10.5 - 11.0% CO
2
CO - (80 - 100ppm)
CO 10.2 - 10.4% CO
2
CO - (80 - 100ppm)
boiler module
then switch the commissioned
Minimum
8.3 - 8.5%
2
9.0 - 9.5%
2
8.6 - 8.9%
2
is now
500001130/J