Clean tankless water heater inlet filter

Short answer

Once a year, shut off the cold water supply, unscrew the inlet filter, rinse the screen under running water, and reinstall.

Priority: Medium
Difficulty: DIY
Time: 15 min
How often: Once a year

Why It Matters

The cold-water inlet filter catches sediment that would otherwise foul the heat exchanger and slow water flow. A clogged filter reduces hot water output and can trigger error codes.

Tools

Bucket

How to Do It

Consult your water heater's manual to locate the cold-water inlet filter, typically found at the bottom of the unit.
Place a bucket under the inlet to catch any residual water.
Shut off the cold water supply to the heater.
Unscrew the inlet filter housing and remove the screen.
Rinse the screen under running water until clear of sediment, then shake off the excess water.
Reinstall the screen and housing, then turn the cold water supply back on.

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Replace water heater anode rod Every 5 years

Part Of

Plumbing Water Heater

Last updated 22 September 2026

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