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Backflow stops and Cleaning pipes Triplex
Post-installation inspections
4 Post-installation inspections
Following installation, the emergency flap and seal integrity (tightness test) must be tested.
4.1 Activating the emergency flap
Only backflow stops type 1 and type 2:
NOTICE
The emergency flap must be open for water to drain. Close the emergency flap if
water backflows, e.g. in extremely heavy rain.
Closing the emergency flap:
Î
Fold up the red lever until it locks (clicks
audibly into place) (1).
Opening the emergency flap:
Î
Press down the red lever until it stops (2).
2.
1.
4.2 Tightness test
Only double backflow stop type 2:
Properly qualified personnel must perform the tightness tests,
Section 1.4 "Personnel qualification".
The test includes simulating a backflow using a test funnel (included in the scope of supply)
to test the seal integrity and functional reliability of the automatic flaps.
The seal integrity of the backflow unit is deemed to be sufficient if less than 500 ml (0.5 l) of
water is needed to top up the test funnel within 10 minutes.
If this is not the case, clean the backflow unit. Coarse deposits will often be the cause.
Repeat the test.
Replace the backflow unit if more than 500 ml (0.5 l) of water still has to be used to top up
within 10 minutes.