Biasi M275V.2024 SM, Руководство по обслуживанию

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GAS VALVE
11 GAS VALVE
11 .1 Function
The gas valve "1" in Figure 11.1 controls the gas inflow to the
boiler burner.
Figure 11 .1
1
By means of an electric command given to the on-off operators
the passage of the gas through the Gas valve can be opened or
closed.
11 .2 Description of the parts
(Figure 11 .2)
2 On-off operators electric connector
3 Gas valve inlet pressure test point
4 On-off operators
5 Minimum boiler power adjustment
6 Maximum boiler power adjustment
Figure 11 .2
6
2
3
5
4
11 .3 Adjustment - Chimney Sweep Function
Warning: isolate the boiler from the mains electrici-
ty supply before removing any covering or compo-
nent .
Each time after measuring the gas pressure, fully
close all tapping points that were used .
After each gas adjustment, the valve adjustment
components must be sealed .
Warning: risk of electrocution .
The boiler is live during the operations described in
this section .
Never touch any electrical parts .
Check the supply pressure before making any adjustment
to the gas valve .
1 Close the gas inlet valve.
2 Remove the front panel of the case and lower the control
panel (see sections "2.2 Case panels" on page 5 and "2.3
Control panel" on page 5).
3 Loosen the internal screw on the Inlet Pressure Test Point "3"
(Figure 11.2) of the Gas valve and connect a pressure gauge
using a suitable hose.
4 Open the gas inlet valve.
5 Read the inlet pressure value and ensure that it is within the
limits given in the table
Gas supply pressures
, of the user/
installation manual. If it does not comply with the required
pressure check the gas supply line and governor for faults
and/or correct adjustment.
6 Switch off the boiler close the gas inlet valve .
7 Disconnect the pressure gauge and close the Inlet Pressure
Test Point "3" (Figure 11.2).
Gas valve adjustment
The person carrying out a combustion measure-
ment should have been assessed as competent in
the use of a flue gas analyser and the interpretation
of the results. The flue gas analyser used should be
one meeting the requirements of BS7927 or BS-
EN50379-3 and be calibrated in accordance with the
analyser manufacturers’ requirements, and have a
current calibration certificate.
8 Fit the probe of the flue analyser in the flue exhaust sampling
point located on the exhaust pipes of the boiler (Figure 11.3).
Figure 11 .3
Flue exhaust
sampling point
Air intake
sampling point
9 Turn on the boiler, switching on the fused spur isolation
switch.
10 Open the gas inlet valve.
11 Turn on the boiler and operate for 2 minuets to pre-heat the
flue, before commencing any adjustments.
12 Make sure that the room thermostat is in the “heat request”
position.