New Toto Dartmouth running

I installed a new Toto Dartmouth as per the advice of this board. I love it. I didn't know what a good flush was until I installed this. However the unit occasionally runs after flushing. It doesn't happen often, but it does happen. There must be a problem with the flapper. Any advice?

When the valve shuts off, where is the water level? It could be adjusted too high and (just) going down the overflow sometimes. The hose needs to be on the overflow using the clip, or it can siphon out water, too. Check the seat where the flapper valve goes to make sure it is smooth and nothing is caught there. Also, make sure the chain isn't too long and getting caught under the flapper or kinking and not letting it go down far enough.

jadnashua said:

When the valve shuts off, where is the water level? It could be adjusted too high and (just) going down the overflow sometimes.

Click to expand...

AND, if the water level is found to be at the top edge of the overflow pipe, take steps to assure yourself that the valve is not failing to completely turn off. Refer to the recent thread, "Toto Ultramax /G-MAX fill valve problem."
Art