Dishwasher spray arm
The part that does all the mechanical work. A blocked jet leaves a wedge of the load dirty, which reads as a machine problem rather than a hole problem.
Precautions
- Check the manufacturer's instructions
Start here
What this is, what goes wrong with it, and where CleaningHQ can help.
Made from
What tends to go wrong
A hard, chalky calcium carbonate deposit left by hard water. Dissolved by acids, essentially untouched by detergents.
Why it is difficult: Water hardness, Crystallisation, Adhesion and cohesion
Fats and oils, which water alone cannot lift. Removed by surfactants, by heat, by solvents, or by alkalis that convert the fat into soap.
Why it is difficult: Why oil resists water, Emulsification
- Dustvia its material
Mostly textile fibres and skin, held by static as much as by gravity — which is why a dry cloth on a plastic surface makes it worse.
Why it is difficult: Static and dust, Mechanical action and abrasion, Why different surfaces get different dirt, Surface roughness
A concentrated water-soluble dye with nothing else in it. Nothing has to be emulsified or dissolved — the only question is whether the surface has taken the colour up.
Why it is difficult: Capillary absorption, Dye migration and colour bleeding
A sticky, yellow-brown tar film deposited everywhere at once. It is the reason a room smells after everything visible has been cleaned.
Why it is difficult: Adsorption of odour molecules, Solubility and polarity
Coloured by turmeric in most prepared mustards, and curcumin is a pH indicator — which is why an alkaline cleaner turns a yellow mark red.
Why it is difficult: pH indicators in stains, Fat-soluble pigments, Photodegradation, Pigment retention
The commonest cleaning problem that is not dirt. The tackiness is the plastic's own additive arriving at the surface, which is why wiping it off works for a week.
Why it is difficult: Plasticizer migration, Damage versus soiling
The science behind this: Solvent crazing, Static and dust, Solvents and polymers, Plasticizer migration
Part of Dishwasher.
In detail
A dishwasher has no scrubbing action at all — the spray arms provide every bit of the mechanical energy in the process, and the chemistry and heat do the rest. That makes them the component whose failure is most often misdiagnosed. A jet blocked by a seed, a label or a fragment of glaze stops covering a sector of the load, so items in that zone come out dirty while everything else is clean, and the owner concludes the machine is failing or the detergent is wrong. Limescale is the second blocker in hard-water areas, building inside the arm and narrowing the jets gradually rather than suddenly. Both are owner-serviceable: most arms unclip or unscrew by hand, are rinsed through under a tap, and have their jets cleared with a cocktail stick rather than anything metal. Two things obstruct the arms without blocking them, and they cause the same symptom — a tall item in the lower basket fouling the upper arm's rotation, and an overloaded basket shielding the surfaces behind it. Spinning each arm by hand after loading takes a second and prevents both.
Related
- Dishwasher spray arm is made from Household plastics
- Dishwasher spray arm is commonly affected by Limescale
- Dishwasher spray arm is commonly affected by Grease
Sources for this page
Sources
Owner's Manual: Dishwashers GSD4500, GSD4800
GE Appliances · Manufacturer documentation
Relied on for: That the spray arms deliver the wash action, that loading must not obstruct their rotation, and that the manufacturer addresses blockage and water distribution. (states this directly)
Verification: a person has read the passage relied on.
Read on — 'Caring for the dishwasher' and the film, cloudiness and marks entries in Troubleshooting Tips. Supports the claim as stated.
Last reviewed by a person on .