Indesit dishwasher leaving white residue on glasses
Indesit DFG15B1 — glasses and plastics come out with a chalky white film. We're in a hard water area and use Finish tablets plus rinse aid. Already cleaned the spray arms and filter. Is it worth adding dishwasher salt, or is this a sign the water softener unit has failed?
1 Answer
A chalky white film on glasses and plastics is very commonly hard-water mineral deposit rather than a serious fault, especially in a hard water area. On an Indesit like this, using all-in-one tablets does not always provide enough softening, so yes, dishwasher salt is often still needed.
1. Check whether the white film wipes off with vinegar If it comes off with a bit of white vinegar on a cloth, that points to limescale/mineral residue rather than detergent damage or etching.
2. Make sure the dishwasher salt reservoir is filled Even with Finish tablets, many machines still need proper dishwasher salt in hard water areas. Table salt must not be used. If the salt reservoir has been left empty, the built-in softener will not cope properly.
3. Check the water hardness setting If the machine’s salt/softener setting is too low for your area, you’ll get deposits. It’s worth checking the instruction book and matching the setting to your local water hardness.
4. Don’t overdose detergent In some cases, using tablets plus extra rinse aid can leave residue if the programme is too cool or too short. Try a hotter full wash and, if possible, reduce rinse aid one step to test.
5. Consider whether the softener may have a fault If you refill salt, set hardness correctly, and still get heavy white deposits after a few washes, then the softener system, salt cap sealing, or regeneration process may have a problem.
Isolate the appliance from the mains before inspecting any internal parts. If it needs testing of internal valves, controls, or the softener unit itself, it’s best handled by a qualified appliance engineer.
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