[bct123]

I have three bathrooms and whenever you flush the toilet in one bathroom the tolet in the other bathroom runs. It also does it when you turn the water on in the bathroom sink. It only does it with the downstairs bathrooms. What is going on?

[speedball1]

whenever you flush the toilet in one bathroom the tolet in the other bathroom runs. It also does it when you turn the water on in the bathroom sink.

Which tells me the level in the tank of the toilet that runs is way too high. And if that toilet's that mich out of adjustment then your other toilets have been neglected also. Let's do this right and check them all.
Check the tank water level, it should be at the mark in the tank or 3/8 to 1/2" below the top of the over flow tube. Now look at the flapper, If it has wavy edges on the flat surface, replace it. The linkage between the flapper and the flush lever should have 1/4" play when the tank is filled. Also, check the small tube coming out of the top of the ballcock and make sure it's connect to and draining into the white overflow tube. More questions? I'm as close as a click. TOM