What Hard Water Does to Dishwashers, Ice Makers, Washers and Water Heaters
Updated
Short answer
Dishwashers
GE: white film on glasses and the tub is most often seen in hard-water areas, partly because modern detergents are phosphate-free, and over time hard-water buildup can cause damage to dishwasher components. GE's fixes are a dishwasher cleaner or a citric acid cycle, rinse aid, and a water softener (GE, GE). Some GE models take a hardness setting from a test strip (GE). Bosch says limescale builds up quickly in hard-water areas, that its E12 code means limescale in the heat pump, and recommends descaling and softening salt where the dishwasher has a softener (Bosch).
Ice makers
GE says minerals build up on a freestanding ice maker's freezing plate until ice cannot release, and that it may need cleaning as often as every six months depending on hardness (GE). Angi notes that ice maker water inlet valves are prone to mineral buildup, making valve repairs common in hard-water areas (Angi).
Washers
Washer inlet valves have small screens that catch sediment. LG's IE (water supply) error list includes inlet filters clogged with sediment and walks through removing and rinsing them (LG).
Water heaters
InterNACHI's life expectancy chart notes that the mineral content of water can shorten the life expectancy of water heaters and clog showerheads (InterNACHI).
What to do
- Look up your number in the hardness table and set any appliance that asks for it.
- Use rinse aid in the dishwasher and run a citric acid or dishwasher-cleaner cycle when film appears.
- Clean freestanding ice makers on the manufacturer's schedule.
- A water softener is the option every manufacturer above mentions; HomeGuide puts a new one at $1,200 to $3,800 (HomeGuide).
Sources: GE Appliances, dishwasher white film; GE Appliances, dishwasher interior staining; GE Appliances, how to set dishwasher water hardness; Bosch, dishwasher error codes; GE Appliances, standalone ice maker cleaning; Angi, ice maker repair cost (updated Jul 20, 2026); LG, washer error code list; InterNACHI, Standard Estimated Life Expectancy Chart for Homes; HomeGuide, appliance repair costs (July 14, 2025)
Quick answers
Does hard water damage dishwashers?
GE says hard-water buildup can cause damage to dishwasher components over time, and recommends rinse aid, citric acid cleaning and a water softener.
How often should I clean an ice maker in hard water?
GE says freestanding ice makers may need cleaning as often as every six months depending on water hardness.
What is Bosch error E12?
Limescale build-up in the heat pump. Bosch says to descale the dishwasher and use softening salt if it has a softener.
Rather have someone fix it?
Tell us the appliance, the brand, the model number and what it is doing. A local technician calls back with a time and a price before any work starts.