Interactive Photo Diagram
Whole-Home Water Filtration
A whole-home filter removes sediment and contaminants from all the water entering your home. Regular filter changes keep it working properly.
Reference checked: component relationships and terminology were reviewed against manufacturer documentation from Pentair. This is original Classic Plumber educational artwork, not a manufacturer drawing.
Tap a numbered marker to learn what that part does.
Overview
A whole-home water filter is installed on the main water line, so every faucet in your home gets filtered water. The filter housing contains a replaceable cartridge that removes sediment, chlorine, and other contaminants before they reach your fixtures. Regular cartridge changes keep your water clean and your water pressure healthy — a clogged filter is a common cause of reduced pressure throughout the house.
How It Works
Water enters the filter housing through the inlet, passes through the filter cartridge (which traps sediment and contaminants), and exits through the outlet to your home's plumbing. The bypass valve allows you to route water around the filter for service. The pressure gauge helps you monitor when the filter is clogged — a significant pressure drop means it's time to change the cartridge.
Key Components
Filter Housing
The canister that holds the cartridge. Unscrews for filter changes.
Filter Cartridge
The replaceable filter element. Replace every 3–6 months.
Inlet Shutoff Valve
Closes water entering the filter for service.
Outlet Shutoff Valve
Closes water leaving the filter for service.
Bypass Valve
Allows water to bypass the filter during cartridge changes. Keep closed normally.
Pressure Gauge
Shows pressure. A large drop indicates a clogged filter.
Common Issues
Low water pressure throughout house
Clogged filter cartridge. Check the pressure gauge and replace the cartridge.
Leaking at the housing
Worn or dry O-ring. Turn off water, replace the O-ring, lubricate with silicone grease.
Housing won't unscrew
Seized O-ring. Use a filter wrench. Don't overtighten when reinstalling.
Water not being filtered
Bypass valve left open. Close the bypass and open the inlet/outlet valves.
Maintenance Tips
- Replace the cartridge every 3–6 months, or when pressure drops. Note the date on the filter.
- Always turn off the inlet valve and relieve pressure before opening the housing.
- Lubricate the O-ring with food-grade silicone grease — never petroleum-based products.
- Don't overtighten the housing — hand-tight is usually enough with a lubricated O-ring.