Whole House Systems Finder

Finding a water system for your home shouldn't be a hassle.
Search below by one, or several criteria, to find the solution that best matches your needs.

Search By Dimensions

Search By Part Number

Selecting Your Dimensions

Household Size:
Average number of people living in the home.


Flow Rate Range:
The range the system can perform up to (gpm).

Fitting Size:
The connection size that the system will use.

Contaminant Issue:
Select the primary issue in your water.

Do I Need a Whole House Filter?

Whole home filters are not always necessary but they do provide a wide range of benefits. Installing a whole house filter to your water main before it flows to your appliances and faucets helps extend appliance life and efficiency. Even large micron sediment filters can significantly reduce the amount of sediment that could accumulate in your water heater or plumbing. Since that filtered water is running through your entire home, with just one filter you can pretreat all the water running to each point of use (faucet, showerhead, and appliance) location. This will in turn also improve the ability of any other filters you may have installed, including fridge filters, undersink filters, reverse osmosis systems, water softeners, and more!

Already have a whole house system and looking to replace your filter? Try our Whole House Filter Finder to search by filter size, contaminant issues, micron rating, flow rate, and media type! If you have any questions reach out to our water experts at 1-800-277-3458, we're happy to help.

Filter Sizes, Which is Right for My Home?

When selecting a filter size, the decision is dependent on the water needs of your home. Larger filters will generally require higher flow rates to keep up with water demand. Micron rating and media will also play into this eqaution. Finer filtration is commonly accompanied by a lower flow rate, so if you dont want to compromise on micron rating but expect that your home may require more than the achievable flow rate, then a larger filter of the same media and micron rating may be necessary.

Universal Filter Housing Reference Sizes:

The filter housings shown below represent the most common whole house filter housing options. Note: sizing may differ slightly between housing options and by brand, but should be relatively similar. Below each sizing chart is the filter size that should be used with that corresponding housing. If you are currently using a filter housing not listed below please reach out to our support team at 1-800-277-3458, we will gladly assist you with finding the right filter for your system.

Filter Size: 10 x 2.5 inches

Filter Size 10 x 4.5 inches

Filter Size 20 x 2.5 inches

Filter Size 20 x 4.5 inches

Flow Rate Restriction Example:

Question: I have a whole house filter at the point of entry for our house. We are on a well. I have a 20 GPM filter. I'd like to replace it with a 3 GPM filter. Will I be compromising our flow rate into our house with the lower GPM filter? Stated another way, will the flow rate at the point of use be reduced to a trickle?
Answer: Point of entry systems filter water for your shower, hot water heater, dishwasher, etc. The flow rate for your filter should meet the water demand of each of these appliances measured in gallons per minute. Some typical ratings are listed below.
  • Shower: 2.5 - 5 GPM
  • Dishwasher: 3 GPM
Larger homes require higher flow rates and a filter with a flow rate less than 10 GPM may cause pressure loss during peak use.

The take away is that the filter size and media you select will depend on the demands of your home. If you would like help making this decision please reach out to our dedicated support team at 1-800-277-3458 or email us at support@discountfilterstore.com. We would be happy to assist you.

How Do I Replace My Whole House Filter?

Systems can be cleaned and replaced in different ways we would recommend the following steps for replacing your filter:

  1. Turn off the water supply/water feed to the unit.
  2. Press the pressure relief button (if present) and run water faucets to reduce pressure in the line.
  3. Unscrew the housing and remove o-ring (whipe clean and set aside).
  4. Discard used filter cartridge.
  5. Wash the housing with dish soap and warm water using a nonabrasive sponge or cloth. Then rinse thoroughly.
  6. Lubricate o-ring with clean silicone grease. Change the o-ring if any damage, cuts, or degradation are present. Then insert the o-ring in groove of the housing. Make certain the o-ring is seated level in the groove. NOTE: This step is important to ensure a proper housing seal.
  7. Insert new filter cartridge.
  8. Screw housing onto the cap and hand tighten. While installing make sure the cap standpipe slips into the cartridge. Do not overtighten.
  9. Turn on water supply and check for leaks before leaving installation.

Replacement Accessories

For replacement filters try our filter finder options above or visit our Whole House Water Filter Replacements page.
For replacment o-rings you can check out the O-ring and Lubricant page or select from the following recommendations:
In the event you have misplaced or lost an existing housing wrench, feel free to peruse our Water Filter Wrenches options to find the best wrench for your housing.