Vaillant ecoTEC plus VU GB 656/4-5 A Installation And Maintenance Instructions Manual page 20

6 Start-up
Conditions: The product design is compatible with the local gas group
▶
Proceed as described below.
6.12.2 Checking the leak-tightness of the flue gas
installation and flue gas recirculation
1. Check the flue gas installation is intact in accordance
with the latest gas safe technical bulletin and informa-
tion supplied in the installation instructions.
2. For extended flue gas installations check for flue gas
recirculation using the air analysis point.
3. Use a flue gas analyser.
4. If you discover CO or CO
the leak in the flue gas installation or for signs of flue
gas recirculation.
5. Eliminate the damage properly.
6. Check again whether the supply air contains any CO or
CO .
2
7. If you cannot eliminate the damage, do not start up the
product.
6.12.3 Checking the gas flow rate
The boiler is fitted with a multifunctional automatic gas valve
which ensures that the precise air/gas ratio is provided under
all operating conditions.
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
46,0
65,0
Conditions: 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.
Conditions: 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.
20
in the supply air, search for
2
H gas in m³/h
−10 %
Nom. +5 %
4,87 5.13 4,38
6,88 7,24 6,19
6.12.4 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 isolator cock.
1
2
3. Undo the sealing screw (1) that is marked with in on the
gas valve.
4. Connect a digital pressure gauge or U-tube manometer
(2).
5. Open the gas isolator cock.
6. Start up the product with the check programme P.1.
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 (1)
complies with the requirements.
–
Permissible gas flow pressure for operation with
G20 natural gas: 1.6 ... 2.3 kPa (16.0 ... 23.0 mbar)
9. 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.
Conditions: Gas flow pressure not in the permissible range
Caution.
Risk of material damage and operating
faults caused by incorrect gas flow pres-
sure.
If the gas flow pressure lies outside the per-
missible range, this can cause operating
faults in and damage to the product.
▶
Do not make any adjustments to the
product.
▶
Check the gas installation.
▶
Do not start up the product.
▶
If you cannot correct the failure, notify the gas supply
company and proceed as follows:
▶
End the check programme P.01.
▶
Allow the boiler to cool down by allowing pump overrun
to operate for a minimum of two minutes.
▶
Close the gas isolator cock.
Installation and maintenance instructions ecoTEC plus 0020214491_01