BoilerBuying Guide2026-02-24
Hard Water and Your Boiler: What to Know
Hard water deposits scale that reduces hot-water performance and triggers faults.
In hard-water areas, scale is a leading cause of reduced combi performance and faults.
The problem
Minerals deposit scale inside the plate heat exchanger and pipework, reducing hot-water flow, causing fluctuating temperatures and error codes.
The fix
Regular descaling restores performance, and a water softener or scale reducer slows build-up in hard-water homes.
Key takeaways
- Scale reduces hot-water performance
- Causes fluctuating temperatures
- Descale regularly
- A softener slows build-up
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