The first component is an on/off valve, which has female pipe thread connections on both inlet and outlet. This means that it will require a male pipe thread connector, rather than a hose thread. Next comes the 24 volt automatic valve which may already have a built-in vacuum beaker or anti-siphon. If not, then one must be installed separately. Then, the fertilizer dispenser, which is followed by the ‘Y’ filter.
The last item needed before you complete the head assembly is the pressure regulator. Most pressure regulators for this size of system have female pipe threads on both sides, allowing them to connect to the filter without the use of an adaptor. The pressure regulator is placed on last so that the pressure going out to the lines is at the desired level. The poly tubing is connected to the pressure regulator. The regulator should be placed ahead of the ‘Y’ filter and fertilizer dispenser, if you have pressures that exceed 60 PSI. Depending on the parts you decide to use, you may find that connections will need to be made between incompatible fillings. There are adaptors available to solve this problem.