My saniflo-plus system is about 12 years old..recently it stopped draining the toilet, etc. I pulled the cover off the pump and checked for blockage and spun the cutter blades...The motor just hums....do I need to replace the entire encased pump assembly?? Help

Hello
im a plumber and it sounds like your 110 drainage pipe is blockt.
your 40mm sink pipe, drains into your 110mm same as your 110mm toilet and 50mm shower, so the best solusion wil ...sory u must eather by drain rods and clean your 110mm pyp by a inspection i. bt that will be more exspensive then to just call a plumber to rod it for u. cos if ur toilet shower and sink is bloking it must be your 110mm pyp

If it blows the fuse out or trips the GFI then there is a problem with the pressure chamber. May is cracked or broken and if water enters the pressure chamber it will trip the GFI and the pump will not turn on or it will hum. You may have to replace the complete pressure chamber.