Search guides

Fix a recirculation pump that makes noise

We'll confirm the noise source, check for air and mounting, then bleed, tighten, or replace the pump—or tell you when to call a pro.

Troubleshooting · Home maintenance
15–45 min
What you'll need
  • Screwdriver and wrench set
  • Replacement recirculation pump (if pump has failed)
Step 1 of 7

Quick triage — pick your path

Get started

Choose the option that matches what you see. You can jump straight to that section.

Show full guide

Steps

Goal: Confirm the noise source, check for air and mounting, then bleed, tighten, or replace the pump.

  • Locate the recirculation pump. Listen when it runs. The noise should be loudest at the pump.
  • Good: Noise at the pump—proceed to Bleed air or Tighten mounting based on the noise type.
  • Bad: Noise elsewhere—check pipes or other equipment.

Bleed air

Goal: Release trapped air that causes grinding or gurgling.

  • Shut off the pump. Open the bleed screw or bleed valve on the pump. Let air escape until water flows. Close the screw.
  • If the system has high points, open bleed valves there with the pump off. Close when water flows.
  • Restore power and run the pump. If the noise stops, air was the cause.
  • Good: Noise stopped. Fix complete.
  • Bad: Noise continues—check mounting or replace the pump.

Tighten mounting

Goal: Stop rattling from loose mounting or vibration.

  • Check the mounting bolts or bracket. Tighten if loose. Add rubber isolation pads if the pump vibrates against the pipe.
  • Restore power and run the pump. If the rattling stops, the fix worked.
  • Good: Noise stopped. Fix complete.
  • Bad: Noise continues—check for debris or replace the pump.

When to get help

Call a plumber if:

  • Bleeding and tightening do not stop the noise.
  • The pump is leaking.
  • The pump needs to be replaced.
  • You are not comfortable with plumbing.

Verification

  • The pump runs quietly when circulating.
  • No grinding, gurgling, or rattling.
  • Hot water reaches fixtures as expected.

Escalation ladder

Work from the device outward. Stop when the problem is fixed.

  1. Confirm noise source Verify the noise comes from the recirculation pump.
  2. Bleed air Bleed the pump and high points in the loop.
  3. Tighten mounting Tighten loose bolts; add isolation if needed.
  4. Replace pump If bleeding and tightening do not work, replace the pump.
  5. Call a pro Pump still noisy, leaking, or not comfortable—call a plumber.

What to capture if you need help

Before calling support or posting for help, have these ready. It speeds everything up.

  • Type of noise (grinding, gurgling, rattling)
  • Whether bleeding reduced the noise
  • Whether mounting was loose
  • Pump model
  • Steps already tried

Does the noise come from the recirculation pump?

Listen at the pump when it runs. The noise should be loudest at the pump.

Locate the recirculation pump. Listen when it runs. Good: noise loudest at pump—pump is the source. Bad: noise elsewhere—check pipes or other equipment.

Yes No

You can change your answer later.

Is the noise grinding/gurgling or rattling?

Grinding or gurgling often means air. Rattling often means loose mounting.

Grinding or gurgling: bleed air from the pump and high points. Rattling: tighten mounting bolts; add isolation. Good: try the fix for that noise type.

Grinding or gurgling Rattling

You can change your answer later.

Did bleeding air stop the noise?

Bleed the pump and high points in the loop. Restore power and run the pump. Yes: fix complete. No: check for debris or replace the pump.

Yes No

You can change your answer later.

Did tightening the mounting stop the noise?

Tighten mounting bolts. Add rubber isolation if needed. Yes: fix complete. No: check for debris or replace the pump.

Yes No

You can change your answer later.

Fix complete

The noise has stopped. Monitor for a few days to confirm.

Done

Replace the recirculation pump

Bleeding and tightening did not work. The pump may have a worn impeller or bearing. Replace the pump. Call a plumber if you are not comfortable.

Done

Call a plumber

Call a plumber if the noise continues after bleeding and tightening, the pump is leaking, or you need to replace the pump.

Done

Reviewed by Blackbox Atlas

Frequently asked questions

Why would a recirculation pump make noise?
Common causes: air in the pump or pipes, loose mounting or vibration, a worn impeller or bearing, or debris in the impeller. Air causes grinding or gurgling; loose mounting causes rattling; worn parts cause grinding.
Can I fix a noisy recirculation pump myself?
Yes, you can bleed air from the pump, tighten loose mounting, and check for debris. Replacing the pump requires shutting off water and plumbing—call a plumber if you are not comfortable.
When should I call a plumber for a noisy recirculation pump?
Call a plumber if bleeding and tightening do not stop the noise, the pump is leaking, the pump needs to be replaced, or you are not comfortable with plumbing. A pump that grinds continuously may be failing.

Rate this guide

Was this helpful?

Continue to