All about meCombiBoost boosts the mains water supply to combination boilers up to 10 litres per minute.It sits directly on the incoming mains water and boosts water flow making it an ideal solution for properties with low mains supply. This inline pump should be installed directly onto the incoming mains using 3/4 BSP to 15mm or 22mm fittings either after the stop tap or before the boiler applianceNeed to know . Boosts mains water flow up to 10 l/min . Improved shower performance . Quicker bath fill . Stronger flowing taps . Flow indicator lights . WRAS Approved . Fittings kit available . 1 year warranty .