Side-by-Side Water Hardness Calculator

Compare Water Hardness

Analyze real-time PPM, Clark degrees, limescale risk, and dishwasher salt settings between any two UK postcode sectors.

Water Quality Comparison Analysis

Executive Summary: Sector KT20 9 vs Sector SW1A 1

Comparing tap water mineral concentration between Sector KT20 9 (SES Water) and Sector SW1A 1 (Thames Water) reveals a water hardness difference of 15 PPM. Sector KT20 9 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 KT20 9 requires setting H04 whereas Sector SW1A 1 recommends setting H04.

Sector KT20 9 has 15 PPM LOWER water hardness than Sector SW1A 1

Lower PPM indicates softer water, reduced limescale risk, and lower detergent usage.

Water Metric
Sector KT20 9Outcode: KT20
Sector SW1A 1Outcode: SW1A
Hardness (PPM)
260 PPM
275 PPM
Clark Degrees
18.2 °Clark
19.3 °Clark
Classification
Hard
Hard
Bosch Salt Setting
H04
H04
Water Supplier
SES Water
Thames Water
Postcodes Covered
20 postcodes
66 postcodes