The short answer
Most abnormal noise on an Almison dishwasher comes from the sump: a fragment of glass, a cherry stone or a chip of plastic riding the impeller. That is an owner fix and it takes a quarter of an hour. A hum with no water moving is a stalled drain or circulation pump and is a different, heavier job.
Symptoms, and the ones that mean something else
- Grinding or rattling during the wash phase — Something hard is in the filter housing or has passed it and is meeting the impeller.
- A hum with no water sound at all — The motor is energised and not turning. Do not keep restarting the cycle to see if it clears.
- Knocking that stops when you open the door mid-cycle — The spray arm is striking a tall item. It sounds mechanical and is entirely a loading problem.
- A high whine that rises through the cycle — Bearing wear in the circulation pump. It grows over months rather than failing overnight.
- NEAR MISS: a thump as the machine changes phase — The drain valve seating is normal on this class of machine and is not a fault.
Causes, most likely first
- Debris in the sump or filter — First on any dishwasher of this construction, because the coarse filter is a basket rather than a barrier and small hard fragments walk straight through it.
- A spray arm fouling the load — Second, and the reason a technician always asks what was in the top rack. It is free to prove: spin the arm by hand with the rack loaded.
- Worn pump bearings — Third. Slow to arrive, unmistakable when it does, and the point where the noise becomes a parts job rather than a cleaning job.
- Loose mounting or an unlevelled cabinet — Fourth. A machine that has worked itself out of its cabinet clips transmits every normal vibration into the worktop.
The order to work in, and why
- Open the door mid-cycle and listen to where it stops — Free, and it separates a load problem from a machine problem immediately.
- Pull the filter and turn the sump by hand — The debris check is the highest-yield thing you can do and needs no tools.
- Spin each spray arm with the racks in place — Any contact you can feel is contact the pump has been fighting all cycle.
- Feel the cabinet sides for movement while it runs — Only worth doing once the inside is clean and clear.
Steps up to the stopping point
- Remove the lower rack, lift out the filter assembly and wash it — Fragments hide under the coarse basket lip. Run a finger round the sump rim as well.
Tools: washing-up liquid, brushAbout 15 min
- Turn the impeller gently by hand — It should move freely and stop against nothing. Grit under it will be obvious the moment it turns.
Tools: glovesAbout 5 min
- Rotate both spray arms and clear the jets — A blocked jet unbalances the arm, and an unbalanced arm knocks. A cocktail stick clears most jets.
Tools: cocktail stickAbout 10 min
- Check the cabinet fixings and the levelling feet — Tighten what has loosened. Stop here if the noise persists with a clean, clear, level machine.
Tools: screwdriverAbout 15 min
Power off, panels later
Safety
Unplug the appliance or switch off its breaker before removing any panel or reaching past the sump — a capacitor can hold a charge after the power is off. Broken glass is the real hazard in a noisy dishwasher: wear gloves in the sump, and never sweep a hand blindly under the filter housing. Leave the door catch alone; the machine stops when the door opens for a reason, and that behaviour is what makes the mid-cycle listening test safe in the first place.
Where the owner fix ends
Call when the machine hums but nothing turns, because a stalled pump that keeps being restarted burns its winding and turns a pump job into a pump-and-board job. Call also for a whine that has been growing for weeks, since a bearing that is audible from across the room is already shedding into the sump. A clean, level machine that still knocks needs somebody who can watch the arm under load with the door defeated on a service jig, which is bench work and not kitchen work.
Same problem, other brands
Scope of this page
This page treats the Almison dishwasher as a class and does not descend to one family or one model line. It carries no part numbers, no pump specifications and no exploded views, because those differ between builds under this badge and a wrong reference wastes a Saturday. Where a family- or model-specific page exists it will name the sump layout and the filter type for that build, and it is the better answer for a known model. Integrated cabinet fittings are the kitchen fitter's domain rather than the appliance's.
Other faults on this machine
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
