Once you have planned for how many zones your irrigation system will require, and you have built your tap connection, you will need to install an irrigation manifold. The role of the manifold is to distribute the water through each valve to each irrigation zone, which are automatically operated by the irrigation controller.
This How-To Guide uses PVC Fittings which require a bit more planning & attention to detail, because PVC Glue dries fast & once set, there’s no making adjustments. But they are a cheaper, more durable option in high pressure situations than Threaded Manifold Fittings. PVC Manifolds, while trickier to install, minimise the number of potential leak points by having glued connections.
What You’ll Need
- PVC Pipe
- PVC Pipe Cutters
- PVC Plain Fittings (Tees, Crosses, Elbows depending on configuration)
- PVC Valve Sockets (with 25mm Male Thread for Solenoid Valves)
- PVC Cap
- Primer
- Glue
- Black Marker
- Teflon Tape
- Multi-Grips
- Solenoid Valves
- Valve Box
Instructions
1. Pre-Installation
Lay Out PVC Fittings into your desired configuration. Dig a hole according to size of manifold and valve box. The water supply pipe should be set at a height for comfortable installation of valves inside the valve box.
2. Cut PVC Pipe
For each join between those PVC Fittings, cut a 6cm piece of PVC Pipe which will be used to connect them. This will provide enough room for both a solid join & solenoid installation.
3. Remove Pipe “burr”
Cutting the pipe will leave a raised or ‘burred’ edge. So using the blade of your cutters, scrape off the burr around the edge of each cut piece. This will ensure a lock tight seal when gluing.
4. Prime PVC Pipe
Apply the Primer to both the outside of you PVC pieces and the inside of your fittings so it’s ready for gluing.
5. Pre-Mark PVC Pipe & Fittings
Using a black marker at the edge of each fitting and along the 6cm PVC pieces, draw guidelines to ensure manifold is straight when glued.
6. Glue Manifold Together
Starting at the water supply connection, Glue PVC Fittings together, excluding the Valve Sockets. One join at a time, apply glue to the outside of your pipe first, with just a little inside the fitting. Push on & rotate to align up the guidelines left earlier. Allow yourself 15-20mm to rotate, the rotation is important for a solid seal.
7. Screw Valve Sockets to Valves
Apply Teflon Tape to Valve Sockets & screw them into each Solenoid Valve using Multi-Grips.
8. Glue Valves to Manifold
Glue Valve Sockets to Manifold. Again, push on & rotate to align with guidelines.
9. Install Valve Box
Place Valve Box over manifold & fill in surrounding hole. If cut outs need to be made in the side of the box to allow pipe access, that is very much accepted practice.
10. Let PVC Joins Set Overnight
Before you start using your manifold, make sure you let all PVC joins cure overnight which will allow for a long lasting watertight seal.
