Vaillant ecoTEC exclusive 627 Installation And Maintenance Instructions Manual page 28

9.13.2 Checking the gas flow rate
The gas flow rate has been set during production and does
not require adjustment. With the front casing fitted check the
gas flow rate of the boiler as follows:
▶
Start up the product with the check programme P.01.
▶
In addition, ensure that maximum heat can be dissipated
into the heating system by turning up the room thermo-
stat.
▶
Wait at least 5 minutes until the boiler has reached its
operating temperature.
▶
Ensure that all other gas appliances in the property are
turned off.
▶
Measure the gas flow rate at the gas meter.
▶
Compare the measured values with the corresponding
values in the table.
Qnw from the data
plate
15.3
18.4
24.7
25.7
28.6
30.6
35.7
Condition: Gas flow rate not in the permissible range
▶
Check all of the piping and ensure that the gas flow rates
are correct.
▶
Only put the product into operation once the gas flow
rates have been corrected.
Condition: Gas flow rate in the permissible range
▶
End the check programme P.01.
▶
Allow the boiler to cool down by allowing pump overrun to
operate for a minimum of 2 minutes.
▶
Record the boiler maximum gas flow rate onto the
Benchmark gas boiler commissioning checklist.
9.13.3 Checking the gas flow pressure
1. Ensure that the gas inlet working pressure can be
obtained with all other gas appliances in the property
working.
2. Close the gas stopcock.
28
H gas in m³/h
−10%
Nom. +5%
1.62 1.70 1.46
1.95 2.05 1.76
2.61 2.74 2.35
2.72 2.86 2.45
3.03 3.18 2.73
3.24 3.40 2.92
3.78 3.97 3.40
1
2
3. Use a screwdriver to undo the sealing screw of the test
nipple (1) at the gas valve assembly.
4. Connect a manometer (2) to the test nipple (1).
5. Open the gas stopcock.
6. Start up the product with the check programme P.01.
◁
S.93 is briefly displayed.
◁
If the display switches to S.04, the product is ready
for the measurement.
7. In addition, ensure that maximum heat can be dissip-
ated into the heating system by turning up the room
thermostat.
8. With the boiler operating at full load check that the gas
inlet working pressure at the reference test point com-
plies with the requirements.
9. Measure the gas flow pressure in comparison with the
atmospheric pressure.
–
Permissible gas flow pressure for operation with
natural gas H: 1.3 to 2.3 kPa (13.0 to 23.0 mbar)
–
Permissible gas flow pressure for operation with
liquefied petroleum gas P: 2.3 to 4.3 kPa (23.0 to
43.0 mbar)
10. Should the pressure recorded at the reference test
point in the boiler be lower than indicated check if there
is any blockage in the pipework or if the pipework is un-
dersized.
11. Decommission the product.
12. Close the gas stopcock.
13. Remove the manometer.
14. Tighten the screw on the test nipple (1).
15. Open the gas stopcock.
16. Check the test nipple for gas tightness.
Installation and maintenance instructions ecoTEC exclusive 0020193966_04