Dear Dougie, Yes it is probably the float switch. This is located where the power cable enters the Saniflo box. The rubber cover on the base should be flexible, but over time, depending on what you have entering the macerator and the hardness of the water, it can get covered in soap and calcium. Lift out the macerator motor with the float switch and clean the base. Now it should operate correctly. Good luck.
Mr Fix-it, The Plumber, June 2010
