Mixer tap

A hot water outlet that blends boiler water with fresh cold water on its way out — producing cooler, better-tasting water than the raw boiler output.

Why it matters — Raw steam-boiler water sits in the boiler all day, picking up mineral character and getting tannic. A mixer tap produces water around 90 °C with fresh character — much better for long blacks and teas.

Good to know

• Mixer taps are common on La Marzocco GS3 and many higher-end commercial machines.
• The blend ratio is usually fixed at the factory but can sometimes be adjusted.