The short answer
Odour in a BlueStar dishwasher comes from the filter, the door seal and the drain line, and on a built-in the drain line matters more than owners expect because it shares a trap with the sink. A machine that smells of drains rather than of stale food is telling you about the plumbing under the sink, not about the tub.
What you are seeing
- A stale or sour smell when the door is opened
- A sewer-like smell that is stronger at the sink than in the tub
- Grey or pink film on the filter, the seal or the tub floor
- Clean dishes that take on a smell after standing in the machine
- A smell that returns within days of a thorough clean
- A near-miss symptom: a burnt or hot-plastic smell, which is an electrical warning and belongs on the electrical safety page
- Body: What the smell is like tells you where to look: A stale or sour smell when the door is opened. A sewer-like smell that is stronger at the sink than in the tub. Grey or pink film on the filter, the seal or the tub floor. Clean dishes that take on a smell after standing in the machine. A smell that returns within days of a thorough clean. A near-miss symptom: a burnt or hot-plastic smell, which is an electrical warning and belongs on the electrical safety page.
Causes, most likely first
- A loaded filter and sump — Why: this holds more residue than anywhere else in the machine and is the first thing to remove and wash.
- A drain hose without a high loop — Why: without a rise above the machine, trap gas and sink water sit against the tub, which is exactly the sewer smell that is worse at the sink.
- Biofilm in the door seal channel — Why: the seal is outside the spray path entirely, so only a cloth reaches it, and the bottom corners hold the worst of it.
- A stale disposal — Why: the machine discharges into it, so a neglected disposal carries its smell straight back to the dishwasher.
- The door closed immediately after every cycle — Why: a sealed damp tub is the condition biofilm needs, and leaving the door ajar prevents more odour than any product removes.
- Residue inside the spray arms — Why: the arms hold film that reseeds the smell after the tub itself has been cleaned.
- Body: Ranked for a built-in machine sharing a trap with the sink: First, A loaded filter and sump: this holds more residue than anywhere else in the machine and is the first thing to remove and wash. Second, A drain hose without a high loop: without a rise above the machine, trap gas and sink water sit against the tub, which is exactly the sewer smell that is worse at the sink. Third, Biofilm in the door seal channel: the seal is outside the spray path entirely, so only a cloth reaches it, and the bottom corners hold the worst of it. Fourth, A stale disposal: the machine discharges into it, so a neglected disposal carries its smell straight back to the dishwasher. Fifth, The door closed immediately after every cycle: a sealed damp tub is the condition biofilm needs, and leaving the door ajar prevents more odour than any product removes. Sixth, Residue inside the spray arms: the arms hold film that reseeds the smell after the tub itself has been cleaned.
What to check, in order
- remove and wash the filter and sump screen, which hold most of the residue.
- wipe the seal channel and the tub lip by hand, since spray never reaches them.
- check under the sink for a high loop in the drain hose, because a sewer smell is a plumbing symptom rather than a tub one.
- clean the disposal, then finish with a hot empty cycle and a proprietary cleaner.
- Body: Clean by how much residue each place holds, then fix the plumbing cause: First, remove and wash the filter and sump screen, which hold most of the residue. Second, wipe the seal channel and the tub lip by hand, since spray never reaches them. Third, check under the sink for a high loop in the drain hose, because a sewer smell is a plumbing symptom rather than a tub one. Fourth, clean the disposal, then finish with a hot empty cycle and a proprietary cleaner.
Checks you can do yourself
- Switch off at the breaker, lift out the filter and sump screen and wash them in hot soapy water — Tools: soft brush, dish soap — Time estimate: a few minutes
- Wipe the door seal channel, the tub lip and the door edge, working into the bottom corners — Tools: cloth, old toothbrush — Time estimate: a few minutes
- Lift each spray arm, rinse it through and clear the jets before refitting — Tools: cocktail stick — Time estimate: a few minutes
- Look under the sink and confirm the drain hose rises above the machine before falling to the trap — Tools: torch — Time estimate: a few minutes
- Run the hottest empty programme with a dishwasher cleaner, then leave the door ajar between cycles — Tools: dishwasher cleaner — Time estimate: an hour or more
- Body: Most of this is routine maintenance: Switch off at the breaker, lift out the filter and sump screen and wash them in hot soapy water (soft brush, dish soap; a few minutes). Wipe the door seal channel, the tub lip and the door edge, working into the bottom corners (cloth, old toothbrush; a few minutes). Lift each spray arm, rinse it through and clear the jets before refitting (cocktail stick; a few minutes). Look under the sink and confirm the drain hose rises above the machine before falling to the trap (torch; a few minutes). Run the hottest empty programme with a dishwasher cleaner, then leave the door ajar between cycles (dishwasher cleaner; an hour or more).
Safety first
Safety
Unplug the appliance or switch off its breaker before removing any panel. A capacitor can hold a charge after the power is off. Never mix a bleach product with a descaler or any acidic cleaner in the tub; the combination releases a harmful gas. Never put a hand into a garbage disposal, and ventilate the kitchen when using a strong cleaner. unplug-before-service
When to stop and call a technician
These are more than a cleaning job: The smell returns within days of a full clean and a hot cycle. Water stands in the sump between cycles, which means a drainage restriction. A sewer smell persists after the drain hose has been looped correctly. Any burnt or electrical smell, which means stop using the machine now. The smell returns within days of a full clean and a hot cycle Water stands in the sump between cycles, which means a drainage restriction A sewer smell persists after the drain hose has been looped correctly Any burnt or electrical smell, which means stop using the machine now
Nearest pages of the same kind
What this page does not cover
This page is generalized across every dishwasher sold under the BlueStar name: it separates neither the panel-ready cabinets from the stainless-fronted ones and one control generation from another, and it names no individual model. Where a family- or model-specific page exists it is linked here and it outranks this one for that machine; at present no page beneath this one narrows to a single family, so treat the ranking above as the brand-level pattern rather than a reading of your serial plate. For the other faults that turn up on this machine, start from Common BlueStar Dishwasher Problems.
Related pages
- Common BlueStar Dishwasher Problems
- BlueStar Dishwasher: Abnormal Noise or Vibration
- BlueStar Dishwasher: Does Not Clean or Dry
- BlueStar Dishwasher: Controls, Display or Error Code
- BlueStar Dishwasher: Cycle Will Not Run or Complete
- BlueStar Dishwasher: Door, Latch or Seal Fault
- BlueStar Dishwasher: Will Not Drain
- BlueStar Dishwasher: Electrical, Fire or Gas Hazard
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
