toilet fill valve

Running toilet

Is your toilet running?  It's probably the fill valve.  See the photo.  The float on the fill valve moves up and dow,n controlling the water filling the tank.  At times, a worn fill valve's float will cease to rise to the point of "shutting off" the water.  The result is a toilet that constantly fills or "runs".  Fill valves can be tricky to replace, so you may want to call a plumber.  

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