19
Checking both gas train valves for tightness
A
B
1.
Close the gas shut-off valve.
2.
Undo the screw inside test nipple
B
for supply pressure, but do not
remove.
3.
Undo the screw inside test nipple
A
, but do not remove.
4.
Connect the pressure tester with the
manual pump to test nipple
A
.
5.
Gently activate the manual pump to
build a test pressure of approx.
50 mbar.
6.
Wait approx. 5 min for the tempera-
ture to level out and then observe the
display on the pressure tester:
If the displayed pressure does not
drop by more than 1 mbar within
5 min, then the gas train is tight.
Otherwise there is a leak. If this is the
case, return the gas train to
Viessmann Werke for testing.
7.
After the test, close both test nipples
by tightening the relevant screws.
Danger
Escaping gas leads to a risk of
explosion.
Check the test nipple for gas
tightness.
Checking all gas connections for tightness
Danger
Escaping gas leads to a risk of
explosion.
Always carry out the following
steps.
1.
Insert new gaskets in all gas connec-
tions that have been opened and
tighten afterwards.
2.
Open the gas shut-off valve.
3.
Check the inlet seals of the gas train
for tightness.
4.
Start the burner (see page 6).
5.
Check the seals on the outlet side of
the gas train for tightness.
Commissioning, inspection, maintenance
Further details regarding the individual steps
(cont.)
5692 488 GB
