I had previously asked for help to determine why I was getting hot water from several bathroom faucets with the handle in the cold position. The culprit was a bad/worn cartridge in the shower fixture. It apparently allowed water to flow from the hot side through the cartridge to the cold side (pipe). Perhaps the cold supply went by the shower first, then on to the faucets which may have allowed the hot to mix continuously with the cold. It appears that bad/worn faucet cartridges can be a culprit if you have temperature probems at the faucet.