Washer or laundry room smells like sewer or rotten eggs

A true sewer smell usually comes from the house drain, not the washer: a dried-out trap at the standpipe, a drain hose sealed into the standpipe, a clogged standpipe or a blocked plumbing vent. Musty/mildew smells come from the machine itself (boot, dispenser, tub residue). Separate the two by sniffing the standpipe with the hose pulled out.

Cross-checked ~30 min easyBrands: All

Before you start

Sewer gas in quantity is a health hazard; if the smell is strong throughout the house, refer to a plumber promptly

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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