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Installation and operating instruction
Gas burner WG40…/1-A ZM-LN
7 Commissioning
83300002 1/2019-02 La
45-128
7.1.4 Purging the gas valve train
Open test point into valve 1 [ch. 7.1.3].
Connect an approved vent hose to the test point.
Vent hose must lead to atmosphere.
Slowly open gas isolating valve.
The gas/air mixture in the valve train vents via the hose to safe atmosphere.
Close gas isolating valve.
Remove vent hose and immediately close test point.
Use a test burner to ensure no air is present in the valve train.