What is a thermostatic valve?
Sorry, it's probably a no-brainer answer, but what is this thermostatic valve? A lot of people here on GW are bringing this term up and I don't understand what it is and why people want it.
We are building a house and trying to figure out the ideal set-up for our master shower. Right now, it's configured for one fixed and one hand held fixture. Should it be a slide bar or not? We live in So. Calif and the house will have a tankless water heater. We are also using PEX piping. What is this thermostatic and should we really get this?