Saniflo – a step-by-step installation guide

When converting spaces, such as lofts, basements and cupboards, to new bathrooms it is often the case that the existing drainage infrastructure isn’t within the proximity of the conversion. In this case, a Saniflo macerator can be installed with small bore pipework to discharge the waste to the nearest soil stack.

A range of Saniflo macerators can be chosen depending on the job in hand. A typical en suite will require a unit that can take waste from a WC, a basin and a shower. The Sanislim is a popular model that can handle waste from multiple appliances – including the highest output showers. The following is a step-by-step that can be followed when fitting the majority of domestic macerators.


1 Unpack the box, layout all individual items and instructions and check all items are present.

2 Fit the elbowed, non-return valve on to the top of the macerator.

3 Attach the hose clips, flexi-pipe and pan gasket on to the Saniflo and cable tie them.

4 Using an axe saw, cut the top of the plastic pipe on the top of the unit to expose the hole for connection to the basin.

5 Place the unit behind the toilet – or behind a de-mountable wall if the unit is to be obscured from view. Fasten the hose clip to the pan spigot.

6 Plumb the basin waste into the macerator unit.

7 Connect the small bore, discharge pipework from the macerator to the soil stack, ensuring there is a sufficient fall to the soil stack after the initial rise.

8 Connect the electrics to an un-switched fuse spur*.

9 Manually and visually check all the wastewater inlet connections and joints, including the pan gasket connection

10 Turn on the water and electrical supply to the macerator and test it by throwing sheets of toilet paper into the bowl to ensure it is pumped away.

11 Run the tap while checking all connections for water tightness. The macerator should pump away the washbasin waste. Re-flush the toilet.

12 Demonstrate the system to the customer, highlighting correct usage, and hand over the relevant stickers and guarantee card.

A Sanialarm may also be fitted to the Sanislim pump. This has a level pressure switch that triggers an alarm fixed on the top of the Sanislim if the volume of water exceeds the maximum allowed level. The alarm emits a continuous warning sound, until it is switched off and the problem is rectified.

For more information, telephone (RoI/NI) 00353 (0)46 9733077 or visit

*electrics to be tested by competent electrician