Brown water when washing machine fills

Brown or rust-colored water in household fixture

Quick Answer:

If brown water appears as a load starts, immediately stop the washer mid-fill, capture a small sample in a clean cup, and check whether the brown color is present before any detergent mixes. If the discoloration is only on the hot supply it’s often rust or sediment from the water heater; if it’s on both hot and cold, it may be a supply or pipe issue. Do not run the wash until the inlet water runs fully clear.

Why This Happens

  • Rust or sediment in your water heater can dislodge and flow into the hot inlet, especially if the heater hasn’t been flushed regularly.
  • Corroded pipes or service lines can release brownish particles into both hot and cold supply water.
  • Municipal system work, main breaks or seasonal changes can stir up sediment in the public mains and cause temporary brown water.
  • Older flexible washer inlet hoses that break down internally can also add discoloration.

Step-by-Step What to Do

Step 1 — Stop the washer and preserve a sample

  • Stop the machine mid-fill so detergent does not get into the drum.
  • Use a clean cup or clear glass to catch a small sample directly from the fill hose or faucet. Look at the sample before any soap mixes in.

Step 2 — Identify which supply is affected

  • Run a short tap test: open the hot-only faucet and then the cold-only faucet at a nearby sink to see whether brown appears with hot, cold, or both.
  • If it’s only hot, the water heater is the likely source; if both, the problem is upstream from the heater or in shared piping.

Step 3 — Flush and observe

  • With the washer still off, run the affected faucet on full for several minutes to see if the water clears. Take another sample after flushing.
  • If flushing clears the water, try a short test fill on the washer (no detergent) to confirm the inlet is clear.

Step 4 — Check nearby fixtures and timing

  • Check other taps in the house. If multiple taps show discoloration, it’s more likely a plumbing or supply issue.
  • If the brown water began after recent water work, heavy rains, or changes in use, it may be temporary—see Brown water during seasonal changes for common patterns.

Step 5 — Consider the water heater

  • If the hot side is the only problem and flushing the tap didn’t help, your water heater may have sediment build-up. Flushing the tank can help; for guidance and expectations, see Brown water after water heater drain.
  • If you’re unsure about draining or flushing the heater yourself, stop and call a professional (see next section).

What Not to Do

  • Do not wash clothes until inlet water runs fully clear.
  • Do not add detergent or start a cycle if the water is discolored—stains can set and bleach can make them worse.
  • Do not assume the problem will clear instantly; running the machine repeatedly can spread sediment into hoses and the drum.
  • Do not attempt major water heater or plumbing repairs unless you are trained and comfortable with the equipment—turn off supplies and contact a pro if unsure.

When to Call a Professional

  • If brown water persists after flushing faucets and testing other taps.
  • If discoloration affects both hot and cold supplies and is not limited to a single fixture.
  • If you suspect a failing water heater, corroded pipes, or if visible particles continue to appear.
  • If sewer-smelling water, sudden drops in pressure, or leaks accompany the discoloration—these can indicate more serious issues.

Safety Notes

  • Turn off the washer water supply if you are uncertain about water quality before resuming laundry.
  • Avoid handling heavily soiled clothing with bare hands; use gloves and rinse items in clear water before machine washing if you must salvage them.
  • Do not work on gas water heaters or plumbing that you are not trained to handle—shut off power or gas if instructed by a technician.

Common Homeowner Questions

  • Will brown water stain my clothes? If untreated, sediment can discolor fabrics; do not run a wash until the inlet water is clear.
  • Is brown water dangerous to my health? Usually brown water is from rust or sediment and is not an acute health hazard, but avoid drinking it and call your water provider if concerned.
  • Can I prevent this from happening again? Regularly flushing your water heater, replacing old inlet hoses, and addressing corroded pipes reduce the chance of recurrence.

For more related articles, see the Brown or Rust-Colored Water Events hub.

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