We have always maintained an extensive parts and components list of items for the water treatment systems that we sell and support. Often times the breakdown of a component on a control valve is due to age and normal wear and is usually very easy to replace. In some cases, special tools are required for replacing seals and spacers for instance in the Fleck models 9000 and 2510, but for the most part, replacing parts on softener or filter control valves can be performed with common tools.
Repairing your softener or filter system yourself can save you a great deal of expense but it is important to consider other aspects of your softener/filter before repairing. First, consider the age of the system. For example, if your softener is 20+ years old and you have a control valve with worn piston and seals, you will also want to think about the softener’s media. Softener media can have a very long lifespan depending on the conditions of your water and how much water flows through it over the years, but after 20 years or even less, the media becomes worn out. Friction due to the hundreds of regeneration cycles through the years will wear the surface of the resin beads down making them in effective. At that point you should also consider the cost of replacing the resin media and the repair parts you need for your controller. Often times these costs will come close to the cost of an entire new softener.
Another example: You have a greensand filter which is only 5 years old but because of the high iron content of the water, the injector is clogged or wore out and the media is likely in need of changing as well. In this case, changing the injector and the media are less than half the cost of a new filter system, but a close examination of the seals and piston should be done at this time as well. All of these components can be replaced at far less than the cost of replacing the entire system.
We do not recommend repairing a very old system. While the media and parts can be a temporary fix, in the long run you save money and time by investing in a complete new system.