How to build an irrigation valve manifold using a manifold kit
This may be one of the easiest things you do in irrigation. Manifolds are great because they simplify installation, maintenance and repair. Everything is in one place and accessible.
There are two types of manifold kits. They both work the same with some design differences. The big difference is the Premium Kit is built out of Schedule 80 PVC. Tough stuff. The Standard Kit is built out of Schedule 40 PVC. Still plenty strong for most applications.
We need a few pieces of information needed before we start. How many valves are you going to need? Do you want to allow for future expansion? Finally, how do the valves you are using connect? Slip (glued) on? Threaded? Union coupler? Once you have these three pieces of information you are ready to start.
Let’s pretend you need three valves but you plan to expand in the future. You will also be using a valve with a female threaded connection. The first thing we would look at is the manifold body. This one has four outlets with female pipe thread (FNPT) connectors. It also has a connector at one end and is open for expansion at the other.
Now we need to connect the manifold to our threaded valve. We need four 1” PVC pipe nipples. Why four when there are only three valves? The extra will go in our future expansion port. These are threaded into the manifold using plumber’s tape. The valve is then threaded onto the open end of the nipple. The valve is now installed. Nothing to it.
This leaves two open ends and one open port. The port is simply capped off. The male threaded open end is for expansion. You can build these with two, three and four port manifolds. If you know you won’t be adding another manifold or running you water line further then you cap it off. The other end is designed for connection with your water supply. The connectors you use will depend on the pipe and design of your system. You may use a standard threaded PVC connector or one of the connectors designed for the system. Fittings for almost any situation can be found HERE.
A general idea of your design is shown in the picture. The important thing to remember about assembling your own manifold is that it is completely customizable to valve number and connection types. It is also more durable than one built out of PVC fittings and pipe, saves time and is expandable. Hard to beat.