Executive Summary: Sector SM4 4 vs Sector SW1A 1
Comparing tap water mineral concentration between Sector SM4 4 (SES Water) and Sector SW1A 1 (Thames Water) reveals a water hardness difference of 15 PPM. Sector SM4 4 has softer water at 260 PPM (Hard) compared to Sector SW1A 1 at 275 PPM (Hard).
Limescale risk and boiler heating efficiency vary based on these mineral levels. Households in Sector SW1A 1 experience higher heating element degradation and kettle scale accumulation due to elevated calcium carbonate density (275 PPM vs 260 PPM).
For home appliance setup, Bosch dishwasher water softener settings should be calibrated accordingly: Sector SM4 4 requires setting H04 whereas Sector SW1A 1 recommends setting H04.