In order for the chemical injector to add chemical to the water stream the pressure being exerted through the injector needs to be lowered. It is important to get the correct injector size combined with foam nozzle size. The larger the hole where the water flow exits the lower the pressure becomes. The higher the water flow of the system the injector is operating on the larger the nozzle hole needs to be. This ensures the pressure is kept low enough to create the vacuum effect required to add chemical to the water stream. If you know the flow and pressure of the system your injector will be working on you can use our interactive chart below to ensure you select the correct products. Click the box where your flow and pressure meet, then select the type of injector you require. You will find the correctly related foam head or foam lance on the products page of the injector you require.

We highly recommend using a chemical filter on the end of your chemical tube. This helps to prevent any unwanted debris possibly entering your chemical injector and causing a blockage. Always check the viscosity of the chemical you are using as this can greatly affect the draw rate of the chemical into the water stream. Dosing of chemical can be adjusted by adding one of the ten nozzles inserts which are provided with each injector.