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1058907-W2-J
Maintenance Procedure - Checkvalves & Strainers
Refer to illustrations in section:
'Installation'
.
Hot water entering the cold supply, or vice versa, indicates that immediate attention
is required. This is performed by removing and cleaning, or renewing the checkvalve
assemblies as necessary.
Blockage of the strainer screens can lead to poor flow performance and reduced
temperature control. It is essential that the strainer screens are cleaned or, if
necessary renewed, as part of the six-monthly maintenance operations.
Removal
1.
Isolate the hot and cold supplies, and move the lever to its mid position to
release any pressure.
2.
Use a suitable spanner to remove the flexible or rigid inlet tails (as applicable)
from the checkvalve assemblies. Retain the sealing washers.
3.
Use a suitable spanner to unscrew the checkvalve assemblies from the isolating
valves. The strainers can then be removed.
Cleaning/Renewal of Parts
4.
Flush the checkvalves with a jet of clean water to remove any debris. The
checkvalves are not serviceable items, and if flushing does not rectify the
problem the checkvalve assemblies must be replaced.
5.
Make sure that the strainers are clean and the integral seal is not damaged.
Replace as necessary.
Re-assembly
6.
Installation of the checkvalve assemblies is a reversal of the removal procedure.
If new checkvalve assemblies are fitted, remove flow regulators if not previously
installed.
7.
Restore the water supplies and check for leaks.
