A saniflo toilet that won't flush properly (the bowl fills up to the top when flushed). The water then drains but really really slowly, over the course of several hours. Can I pour unblocker down it?

It is a problem with the water inlet valve

https://www.plumbersforums.net/threads/how-to-stop-saniflo-toilet-water-running-into-toilet-bowl.106308/

More here.

https://www.google.com/search?q=Saniflow+Sanistar+wall+hung+toilet+won%27t+stop+filling+bowl+with+water


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Water is not draining completely from the toilet line to the sewage tank. If there is a 'low/little slope' section anywhere in that drain line, solids WILL settle and collect there and cause water to back-up in the toilet drain line. Then the toilet will not flush completely or at all until the 'soft blockage' is cleared out and the drain line emptied. Al 'gravity drain' toilets require a free draining/empty drain line that allows flush water to drain unrestricted. A basement toilet has a pump that 'forces' flush water up and out with enough pressure to sometimes force out the 'soft clog.'

If it is going out slowly, get large containers of hot water and flush until it goes out faster. It may take several containers but hot water works wonders and doesn't cost much.

Adjust the float attached to the fill valve. Some simply slide up and down on a racheted adjustment bar. Others screw up and down for adjustment. Flush after each adjustment until the proper fill level is acheived. Make sure there is still a sufficient amount of water at a given level to flush the toilet properly.

flush valve has obstruction and tank is not filling all the way to just below overflow tube.

Sounds like you have a clogged drainline or vent-stack. Fill a large bucket with about three gallons of water and dump it quickly into the bowl. If the drainline/vent is clear, the toilet will "flush" like a gravity toilet and the water will drain from the bowl almost as fast as you can pour it in.

If the water level in the bowl slowly rises (as if it's about to overflow) and then slowly drains, you have a clog somewhere.

All toilets, regardless of their flushing mechanism, require a clear, unoibstructed drain/waste/vent system to extract waste.

If the toilet "flushes" with the bucket of water, you may want to call Flushmate tech support (the number is on top of the tank) or check out the installation and troubleshooting videos at howto.flushmate.com.

Hope this helps.

If there is a air emiten valve on vent ? Remove it than try to see if it works properly. If this works you will need pipe vent outside

If you hear it making noise the motor isnt blown, but it could be clogged.

A quick an easy fix is by filling a 5 gallon bucket with hot water (or warm water) and slowly pouring it into the bowl. The warm water breaks the particles up further, and will help flush the unit out. Make sure you run the water alot after its cleared out (to flush the debris). You can do that by turning on the shower or sink (if connected). If you dont have a shower or sink just keep flushing the toilet.

The water in the tank is not filling to the water line, thereby not providing enough water to flush properly. Adjust the float so that the tank fills to the water line

It sound like you have debris caught in the fill valve. Remove the top where the washer is and put your hand over it and slowly turn the water on to flush the fill valve. Replace the washer with a new one and then replace the top.

If you have the old ball and **** style, replaceing the diaphram is harder so I would recommend replacing it with a fluidmaster fill valve. Hope this helps.