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Make sure the delivery from
rainbank
®
to your home is within the
following pipe length limits:
pipe
Max. pipe
Max. pipe
diameter
length @
length @
6 lpm flow
12 lpm flow
15mm
1m
1m
18mm
90m
27m
20mm
235m
135m
For each bend or tee you should reduce
the above distances by 0.5m.
• We recommend fitting isolation valves
to the rainwater and mains water pipe
so that the rainbank
®
can be easily
and conveniently removed if
required. this saves both wasting
rainwater and having to turn off the
mains supply if the unit ever has to be
removed.
• While rainbank
®
does have an in-built
Dual check back flow prevention
valve, some water authorities require
an additional external back flow valve
to be plumbed into the mains water
delivery line, to prevent any possible
contamination of mains water by
rainwater, particularly if the tank is
partially or fully submerged. check
with your local water authority for their
plumbing guidelines on rainwater
tanks.
• Double check valve assemblies are
available from Davey and should be
installed if the tank is partially or fully
buried.
• Mains water must be limited to below
900kpa.
Type 4 installations. External suction
pump drawing from below ground
tank.
pump inlet should be at least (200mm)
below the lowest water level for reliable
operation.
priming is as for type 1 installations.
If there is a significant amount of water
required to do this it can be a good idea
to fit the highest area of the pipe with an
access plug in a t piece so that the pipe
can be filled more quickly with a bucket
when repriming.
