I am trying to determine the cause of my bathroom faucet turning on without explanation. It is a Delta 500 faucet and it is located on the third (top) level of an 100 yr old, former industrial factory building that was converted into 36 lofts in 1992. The faucet was found running a very small amount, with no known cause. My neighbor reported having a pipe burst in her apartment in the weeks previous, and the weather here in Minnesota has been fluctuating dramatically this winter. The day before the faucet coming on, the temperature reached 48*F and the day of the incident, the temperature dropped to 19*F. I haven't observed any other leaks/drips in my 9 months in the unit. However, in the shower, the water temperature goes from cold to very hot without much in-between temperatures. What possible explanation is there for this faucet coming on? Thank you for your responses!

That Delta has a single handle which operates a cartridge that has seals, seals can go bad. Do you own this unit or rent?