RAIN HARVESTING WDPW01 First Flush Post Wall 300mm Chamber Installation Guide

: June 10, 2024
: Rain Harvesting

Table of Contents

PRODUCT DETAILS
Installation
Product Specifications
Maintenance
CUSTOMER SERVICE
References
Read User Manual Online (PDF format)
Download This Manual (PDF format)

RAIN HARVESTING WDPW01 First Flush Post Wall 300mm Chamber

PRODUCT DETAILS

A high volume first flush diverter, designed specifically for inground applications. Divert the dirtiest water and transform your Rain Harvesting system from “wet” to “dry” with this large volume inground first flush diverter.

This design uses large diameter, 300mm pipe to create the First Flush Diversion chamber – it’s a straight forward design that’s been trusted for years.

Code	Size	Country
WDPW01	90mm 100mm	Australia
WDPW01	90mm 100mm	New Zealand
WDPW01	110mm	India

Installation

WHAT’S IN THE BOX?

Wall/post bracket
Upper bracket
2 end caps
Hose connecter
8 flow control washers
Plastic filter screen
Screw cap with O-ring seal
90mm length of 90mm pipe
Threaded coupling
Stainless steel filter screen
90mm/3” keeper ring (8mm/0.3”) filter
Ball
Ball seat
28mm length of 90mm pipe (Ball seat ring keeper) NB: Stand available separately

TOOLS/MATERIALS YOU MAY REQUIRE

300mm/12” pipe (for diversion chamber)
Tape measure
Marker pen
Saw
Solvent weld glue
Screws
Screwdriver or drill
T-junction
90mm pipe or 100mm Socket / T-Junction
Anchors x3 (for stand)

WALL & POST MOUNT

Screw your wall/post bracket to the wall at your chosen installation point. The outlet of your diverter must sit at least 150mm from the ground when fully assembled. The wall/post bracket supports the lowest end cap of your chamber so select your installation point and attach the wall/post bracket accordingly.
Determine the length of 300mm or pipe required for your first flush diversion chamber using the table below and cut accordingly. Ensure all cut edges are clean and smooth.
Attach the upper and lower end caps to your 300mm pipe by applying solvent weld glue to the socket and pipe before inserting the pipe into the end cap and holding until the glue sets. Repeat for the other end cap. Expect a tight fit.
Place your assembled diversion chamber in the wall/post bracket and support as you fit your upper bracket around the inlet on the upper end cap and screw it to the wall/post.
CAUTION: failure to support the unit in the upright position while attaching the upper bracket could crack the bottom chamber cap.
Select the appropriate flow control washer and fit it into the hose connector with the side marked “TOP” showing. Start by using the Control Washer with the smallest gauge hole (lowest number). Try a larger gauge Washer if experiencing blockages. Save the remaining washers for possible future use.
Insert the plastic filter screen in through the base of the screw cap with O-ring seal and secure by attaching the hose connector and flow control washer.
Apply solvent weld glue to the socket of the threaded coupling and one end of the 90mm length of 90mm pipe. Insert the short section of pipe into the socket and hold until the glue sets. Insert opposite end of this short section inside the lower end cap outlet after applying solvent weld glue.
Place the stainless-steel filter in the lower end cap outlet through the threaded coupling, insert the 8mm keeper ring, then attach the screw cap with O-ring seal (and assembled components) to the threaded coupling.
Place the ball inside your first flush diverter chamber through the upper end cap inlet.
Measure your existing downpipe and cut to create space for a T-junction. Ensure all cut edges are clean and smooth.
Insert the ball seat into the top of the upper end cap inlet, with the narrow end of the seat facing down.
If you’re fitting your diverter to a 90mm T-junction, cut a length of 90mm pipe to connect your diverter and T-Junction. Attach the pipe hard down on top of the ball seat, then attach the T-Junction hard down on top of the pipe.
If you’re fitting your diverter to a 100mm T-junction, attach the 28mm length of 90mm pipe hard down on top of the ball seat and glue in place using solvent weld glue. Fit the T-junction around the upper end cap inlet or, if required, connect the T-junction and upper end cap inlet using an additional length of pipe.
Connect the T-junction to the existing downpipe using solvent weld glue.

STAND MOUNT

Determine the length of 300mm or pipe required for your first flush diversion chamber using the table below and cut accordingly. Ensure all cut edges are clean and smooth.
Attach the upper and lower end caps to your 300mm or pipe by applying solvent weld glue to the socket and pipe before inserting the pipe into the end cap and holding until the glue sets. Repeat for the other end cap. Expect a tight fit.
Place your assembled diversion chamber into the stand, being sure to line up the centre of the chamber outlet with the weld on the stand.
Select the appropriate flow control washer and fit it into the hose connector with the side marked “TOP” showing. Start by using the Control Washer with the smallest gauge hole (lowest number). Try a larger gauge Washer if experiencing blockages. Save the remaining washers for possible future use.
Insert the plastic filter screen in through the base of the screw cap with O-ring seal and secure by attaching the hose connector and flow control washer.
Apply solvent weld glue to the socket of the threaded coupling and one end of the 90mm length of 90mm pipe. Insert the short section of pipe into the socket and hold until the glue sets. Insert opposite end of this short section inside the lower end cap outlet after applying solvent weld glue.
Place the stainless steel filter in the lower end cap outlet through the threaded coupling, insert the 8mm keeper ring, then attach the screw cap with O-ring seal (and assembled components) to the threaded coupling.
Place the ball inside your first flush diverter chamber through the upper end cap inlet.
Measure your existing downpipe and cut to create space for a T-junction.
Insert the ball seat into the top of the upper end cap inlet, with the narrow end of the seat facing down.
If you’re fitting your diverter to a 90mm T-junction, cut an appropriate length of 90mm pipe to connect your diverter and T-Junction. Attach the pipe hard down on top of the ball seat, then attach the T-Junction hard down on top of the pipe.
If you’re fitting your diverter to a 100mm T-junction, attach the 28mm length of 90mm pipe hard down on top of the ball seat and glue in place using solvent weld glue. Fit the T-junction around the upper end cap inlet or, if required, connect the T-junction and upper end cap inlet using an additional length of pipe.
Connect the T-junction to the existing downpipe using solvent weld glue.
Securely bolt the stand and check to ensure that the pipework connected to the top of your First Flush Post/Wall is stable and the unit is not stressed by misalignment.

POLLUTION FACTORS

The following factors can be used as a guide to determining the volume of water to be diverted.

POLLUTION FACTOR FOR THE ROOF

MINIMAL POLLUTION| SUBSTANTIAL POLLUTION
DIVERT 0.5L PER M2| DIVERT 2L PER M2
Open field, no trees, no bird droppings, clean environment| Leaves and debris, bird droppings, various animal matter, e.g. dead insects, skinks, etc.

The above quantum are the results of preliminary testing. Individual site analysis and field testing is required to more accurately assess the quantum to be diverted in each individual case.

DIVERSION FACTOR FOR A FIRST FLUSH WATER DIVERTER

MINIMAL POLLUTION| SUBSTANTIAL POLLUTION
M2 ROOF AREA X POLLUTION FACTOR = LITRES TO BE DIVERTED
Example for a minimal polluted roof of 100m2 100 x 0.5 = 50 Litres to be diverted| Example for a heavily polluted roof of 100m2 100 x 2 = 200 Litres to be diverted
CHAMBER SIZES (300mm Diameter Pipe)

Length Metres| Volume in Litres Contained (approx)
1.0| 72| Add the volume of water held in the pipe section downstream of the Diverter, between the Chamber and the Flow Control Valve/Outlet
1.5| 108
2.0| 144
2.5| 180
3.0| 216
3.5| 252
4.0| 288
4.5| 324
5.0| 360
5.5| 396
6.0| 432

REFERENCE CHART

In-feed from the roof
Tee Junction
To the tank
Pipe Bracket
Chamber Inlet
Ball Seat
Sealing Ball
Diverter Chamber
Filter Screen
Wall/Post Bracket
Chamber Outlet
Screw Cap with O’Ring Seal
Flow Control Valve
Hose Connection
Optional Stand

Product Specifications

First Flush Post/Wall w/ 300mm Chamber

Country	Code	A	B	C	D	E	F	G	H
Australia	WDPW01	90 F	300 F	322	170	71	55	318	14
100 M	300 F	322	170	71	55	318	14
New Zealand	WDPW01	90 F	300 F	322	170	71	55	318	14
100 M	300 F	322	170	71	55	318	14
India	WDPW01	110 M	300 F	322	170	71	55	318	14

All dimensions are in mm unless otherwise stated.

Fitting guide:
F = Female / Socket Fitting
M = Male / Spigot Fitting (Pipe size)
IP = In-Pipe Fitting

Maintenance

It’s important to ensure that your first flush diverter outlet remains clear of any debris. If your outlet becomes blocked, the chamber will not empty and the first flush of water will not be diverted when it rains.

To ensure the flow of water out through your diverter’s outlet, periodically unscrew the outlet to allow debris to fall out. If the diversion chamber is full of water, take care as it empties. Remove the flow control washer, hose connector, keeper ring and filter screens and hose down or wash the screens with clean water. Check the flow control washer for any blockages and remove and clean as necessary.

For best results and minimal maintenance, we recommend installing rain heads such as our Leaf Eater rain heads on all your downpipes to limit the volume and number of leaves and debris that reach your first flush diverter.

A common misconception about collecting rainwater is that all you need is a roof, a tank and some rain. This ‘tanking’ approach cannot always be relied on to deliver the volume – or quality – of water that you require. That is where we can help.

With some thought, your rain harvesting system can provide you with cleaner water and lots of it. Whether you’re completely reliant on tank water or wanting to keep the garden green, our simple steps will help you achieve your goal.

The Rain Harvesting approach to rainwater collection involves using tested and proven products to make quality rainwater available for use in and around your property. You don’t need much to get started and you will be surprised how easy it is to get the most out of your rainwater system.

How can we help you?

COMPLIANCE

AS/NZS 4020:2005 – Testing of products for use in contact with drinking water

DISCLAIMER This product specification is not a complete guide to product usage. Further information is available from Rain Harvesting Pty Ltd and from the installation and Operating instructions. This specification sheet must be read in conjunction with the installation and Operating Instructions and all applicable statutory requirement. Product specifications may change without notice. © Rain Harvesting Pty Ltd