Vaillant ecoTEC plus VU 446/5-5 (H-GB) Installation And Maintenance Instructions Manual page 37

9.13.4 Checking the gas flow pressure
A
B
1. Ensure that the gas inlet working pressure can be ob-
tained with all other gas appliances in the property
working.
2. Close the gas stopcock.
Alternatives 1 ‒ Measuring the gas pressure
3.
at the gas valve assembly::
▶
Undo the test nipple screw (A) on the gas valve
assembly.
▶
Connect a digital manometer or U-tube manometer
(B).
Alternatives 2 ‒ Measuring the gas pressure
3.
at the gas connection::
▶
Undo the test nipple screw (C) at the gas connec-
tion.
▶
Connect a digital manometer or U-tube manometer
(D).
4. Open the gas stopcock.
5. Open the hydraulic circuit's valves.
6. Start up the product with the check programme P.01.
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.
0020261389_03 ecoTEC plus Installation and maintenance instructions
Gas connection pressure/gas flow pressure
difference for natural gas H
VU 446/5-5
(H-GB)
C
VU 606/5-5
(H-GB)
Gas connection pressure/gas flow pressure
difference for liquefied petroleum gas P
VU 446/5-5
(H-GB)
VU 606/5-5
(H-GB)
9. Should the pressure recorded at the reference test
point in the boiler be lower than indicated check if there
D
is any blockage in the pipework or if the pipework is
undersized.
Condition: 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.
▶
▶
▶
▶
If you cannot correct the failure, notify the gas supply
company and proceed as follows:
▶
End 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 stopcock.
▶
Remove the pressure gauge and retighten the sealing
screw (A) or (C) for the measuring nipple.
▶
Open the gas stopcock.
▶
Check the test nipple for gas tightness.
▶
Close the gas stopcock.
▶
Install the front casing. (→ Page 18)
▶
Disconnect the product from the power grid.
▶
You must not start up the boiler.
Permitted gas flow
pressure that is
measured at point
(D)
1.70 to 2.50 kPa
(17.00 to
25.00 mbar)
1.70 to 2.50 kPa
(17.00 to
25.00 mbar)
Permitted gas flow
pressure that is
measured at point
(D)
2.50 to 4.50 kPa
(25.00 to
45.00 mbar)
2.50 to 4.50 kPa
(25.00 to
45.00 mbar)
Do not make any adjustments to the
product.
Check the gas installation.
Do not start up the product.
Permitted gas flow
pressure that is
measured at point
(B)
1.60 to 2.40 kPa
(16.00 to
24.00 mbar)
1.55 to 2.35 kPa
(15.50 to
23.50 mbar)
Permitted gas flow
pressure that is
measured at point
(B)
2.45 to 4.45 kPa
(24.50 to
44.50 mbar)
2.35 to 4.35 kPa
(23.50 to
43.50 mbar)
37