dual flush toilet after flushing sends water back into pan why?

its probably trying to get rid of those super turds of yours. ya manky b******

jim
January 2015

I am not sure what you mean? never the less here goes!
I assume that after the flush the water continues to dribble in to the pan while the cistern is refilling is that correct?. Two things (a) the seal off plunger if a new type internal overflow syphon has slight distortion. (b) The plunger/seal disc has a build up of lime so not closing down fully and needs cleaning. Most siphons are in two parts with the plunger housing separating from the main body fitted to the cistern base so eliminates removal of the cistern to take out the siphon.

So it’s a replace, adjust or clean it job. The siphon unit is twisted to remove look for securing lugs on the frame and twist the siphon in opposite direction to remove. To assist replacement wipe some Vaseline (Petrolium jelly)or liquid soap on the lugs on the siphon body. If the cistern fills and the water then runs in to the pan then it’s the water level in the cistern is running out of the internal over flow. Adjust float screw to lower the level of water.

bob
January 2015