Modular control apparatus for a water treatment system

A modular modular control apparatus for a water treatment system which periodically undergoes a regeneration cycle including a backwash phase and a replenishment phase. The modular control apparatus has a modular design which includes interchangeable timer modules, a drive motor module, a drive mechanism, a valve cartridge unit, a brine valve module and interchangeable brine valve levers. The timer modules are rugged and relatively inexpensive but are not adjustable. Thus, to adjust the predetermined interval between regeneration cycles, a different timer module is installed. The drive mechanism includes two camming elements which in cooperation with an interchangeable lever and brine line sealing module draw a brine solution from the brine tank to replenish the treatment media and refill the brine tank with water to form a new brine solution. The use of interchangeable brine valve levers allows the quantity of brine solution used to replenish the treatment media to be easily adjusted. The valve cartridge includes a spool valve member, an inner piston and a guide assembly, which together form a unitary valve cartridge. The valve cartridge can be removed as a single unit which facilitates the installation, removal and repair of the cartridge. The control assembly also includes a user friendly housing. The front housing member is povotable whereby the valve cartridge and the control modules located in the interior of the housing are accessible from the front of the modular control apparatus. The valve body includes a brine valve module which is removable as a unit form the valve body. The sealing module is also removable as a unit from the brine valve module.