Saniflo overflow

A Saniflo overflow occurs when a macerator pump unit fails to discharge waste at the expected rate and the chamber fills until it spills from the unit or back through the connected fittings. Causes include a partial blockage in the small bore outlet pipework, foreign objects in the cutting chamber, a worn impeller, a failed non-return valve or excessive scale build-up inside the pump body. London flats with macerator-served WCs and basement bathrooms encounter the issue regularly, particularly where wet wipes have been flushed against the manufacturer's instructions. Engineers usually address common causes by isolating the power, dismantling the unit, removing the obstruction and replacing worn parts in accordance with the manufacturer's guidance. Building Regulations Part H1 requires that a gravity WC remains available in the property where a macerator is fitted.