Plumbing question/help (1 Viewer)

I moved into a two story house a year ago. When someone is in the shower on the 2nd floor and another person turns on the water at any sink in the house (1st or 2nd floor), the water temperature in the 2nd floor shower changes drastically. What could cause this and is it something that can easily be fixed?

I'm not a professional plumber, but it sounds like you need to install a new thermostatic mixing valve. It is what regulates the hot/cold water. If it senses a drop in pressure from either the hot/cold side it will adjust the other accordingly.

Most if not all new shower fixtures will come with one, but you can buy it alone.