V4730C/V8730C/V4734C · Edition 05.23
EN-5
5.2 Tightness for applications without without
manual shut-off valve
According North American standards and European
EN161 standards.
This is a test for checking the closure tightness of
the gas safety shutoff valves. It should be performed
only by trained experienced flame safeguard control
technicians during the initial startup of the burner
system.
It is recommended that this test also be included in
the initial commissioning or scheduled inspection
and maintenance procedures.
1
De-energize the control system to make sure no
power goes to the valves.
➔ The de-energized gas valves are closed.
2
Measure inlet pressure continuously during the
test.
3
Close the upstream manual shutoff gas cock.
4
Remove a 1/8” NPT plug from one of the
pressure tap point 3
➔ If a tap 3 is not readily available, use one of the P
taps as an alternative.
5
Install an accurate pressure gauge or manometer
with 1/4” flexible connection tubing (max. internal
diameter 3/16inch, maximum length 2feet)
suitable for the max. inlet pressure.
6
Open the upstream manual shutoff gas cock.
To test V1
7
Energize V2 to purge out the system, wait for
indicated pressure to stabilize at zero.
8
De-energize V2 and simultaneously start a timer
to monitor for pressure buildup in between V1
and V2.
9
Stop the timer when...
– North American standards: Stop the timer when
pressure reaches 50% of the measured inlet
pressure. For example, if the pressure to the
valve inlet is 14” WC. at start of the testing, stop
the timer when the pressure at the manometer
reaches 7” WC.
– European EN161 standard: Stop the timer when
pressure reaches 20% of the measured inlet
pressure. For example, if the pressure to the
valve inlet is 14” WC. at start of the testing, stop
the timer when the pressure at the manometer
reaches 2.8” WC.
10
The recorded time should be longer than the
indicated “minimum time”, refer to page 6
(5.2.1 Time chart allowable valve seat leakage
rate), for the measured inlet pressure and fuel.
11
Alternatively, for shortest test time, the test may
be stopped at the time specified in page 6
(5.2.1 Time chart allowable valve seat leakage
rate). Leakage is within acceptable limits if the
pressure at that time is still less than 50% (North
American standards) / 20% (European EN161
standard) of the measured inlet pressure.
To test V2
12
Energize V1 to pressurize the system, wait for
indicated pressure to stabilize at the inlet
pressure.
13
De-energize V1 and simultaneously start a timer
to monitor for pressure buildup in between V1
and V2.
14
Stop the timer when...
– North American standards: Stop the timer when
pressure reaches 50% of the measured inlet
pressure. For example, if the pressure to the
valve inlet is 14” WC. at start of the testing, stop
the timer when the pressure at the manometer
reaches 7” WC.
– European EN161 standard: Stop the timer when
pressure reaches 80% of the measured inlet
pressure. For example, if the pressure to the
valve inlet is 14” WC. at start of the testing, stop
the timer when the pressure at the manometer
reaches 11.2” WC.
15
The recorded time should be longer than the
indicated “minimum time”, refer to page 6
(5.2.1 Time chart allowable valve seat leakage
rate).
16
Alternatively, for shortest test time, the test may
be stopped at the time specified in page 6
(5.2.1 Time chart allowable valve seat leakage
rate). Leakage is within acceptable limits if the
pressure at that time is still less than 50% (North
American standards) / 80% (European EN161
standard) of the measured inlet pressure.
17
Valves are tight: Remove the test pressure gauge
or manometer from the valve. Remove power to
the system.
18
Using a small amount of pipe sealant on the 1/8”
NPT plug, reinstall the plug in the pressure tap.
After the Test
19
Test with rich soap and water solution to make
sure there is no leak at the test tap and any other
piping connections.
20
Restore the system to normal operation.
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