One of the most common plumbing items we sell to homeowners are our cartridge style whole house water filters. Because so many homes have these filters it is very common for us to be asked “How do I change this water filter?”. This post should help you properly change your water filter without to much trouble and while staying dry!

1. Figuring out the style of filter you have.

We sell two types of cartridge style filters so first you need to decide which you have as the steps are a little different for both. The pictures below show the two styles.

Style 1: A basic filter with NO valve in head. These filters have a red pressure relief button on the top.


Style 2: A valve in head filter. These filters have a valve built into the head so that you can turn the water to “On”, “Off”, or “Bypass”

2. Cutting the water off and releasing pressure.

  • Filter style 1: There should be a valve somewhere before the filter is installed. If it is not close by you may need to turn the water off to the whole house.
  • Filter style 2: With this filter you do not have to cut the water off but doing so can relieve some pressure and make it easier to turn the filter to bypass.

3.  Removing the clear filter housing.

Unscrew housing. (Sometimes it can be hard to get the housing off. Use the wrench that came with the filter or a strap wrench.) Remove large O-ring, wipe it clean, and set aside. Many people do not realize that the black O-ring is in the threads of the filter. Don’t throw the O-ring our with the filter.

4.  Removing the old filter and cleaning housing.

Remove and discard your used filter cartridge. Rinse the housing completely. If you want to be very thorough put a mixture of bleach and water in the housing and scrub clean. Make sure to rinse well.

5. Putting new cartridge in and putting housing back.

Notice the cartridges have a hole in the the middle of them and that the housing has a notch in the bottom. The filter cartridge should sit on this notch. When the cartridge is in place make sure you put faucet grease on the threads and O-ring before threading back on. This will prolong the life of the O-ring and help un-thread the housing next time as well. NO NEED TO OVER TIGHTEN! Many filters break because of over tightening. Let the O-ring do its job. Make sure that you remove the plastic packaging from the new filter cartridge before installing. Believe it or not, we have seen customers leave the plastic on. They will not allow water through if it is not removed.

6. Turning water back on.

Make sure to turn your water supply back on. If you have a Valve-In-Head style housing make sure it is no longer in bypass.


All done!