Carrying Out A Leak Test - Buderus Logano plus GB402 Installation And Maintenance Instructions Manual

9.3.2 Carrying out a leak test

▶ Close the main fuel shut-off valve.
▶ Undo threaded plug on test nipple by two turns.
▶ Push the test hose of the U-tube pressure gauge onto the test nipple.
▶ Open main fuel shut-off valve, read off pressure and note it down.
▶ Close main fuel shut-off valve and read off the pressure again after one
minute.
▶ Calculate the pressure drop per minute from the differential.
Using the calculated pressure drop per minute and the test volume
(V ), refer to the following diagram ( Fig. 41) to see whether the gas
test
valve can still be used.
Fig. 41 Permissible pressure drop per minute for the internal leak test with gas pressure present
[x] Test volume in litres
[y] Pressure drop in one minute in mbar
[1] Range "Valve tight" = applies to new installations
[2] Range "Valve adequately tight" = valve can be used without
restrictions
[3] Range "Valve leaks" = valve may not be used
>> check as described in the following
[]
[] Read-off example: test volume (V
4 mbar/min = range 3 "Tap leaking" = tap may not be used >>
carry out test as described below
If you detect a steep pressure drop of > 10 mbar/minute
at a test volume of (V
(V ). For this, include the pipework to the next shut-off
test
valve in the tightness test and repeat the test using the
new test volume (V
test
If the read-off point for test volume (V
lies within the range "Valve leaks" (see read-off example), carry out the
test described below.
DANGER: Risk of system damage due to short circuit!
▶ Never spray or let leak detection agent drip onto cable
entries, plugs or electrical cables/leads.
▶ Cover areas at risk before testing for leaks.
▶ Check all sealed points in the tested pipework section using a foaming
leak detection agent.
▶ If required, seal any leaks and repeat the test.
▶ If no leaks are found, replace gas train.
Logano plus GB402 – 6 720 804 428 (2012/09)
) 5 litres and pressure drop
test
) of < 1, increase the test volume
test
).
) and pressure drop per minute
test
Fig. 40 Checking internally for tightness
[1] Test nipple
Completing the leak test
▶ Remove hose.
▶ After completing the test, retighten the screw in the test nipple.
▶ Check the test nipple for leaks.
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