How to Regulate the Hot Water Heater

Install temperature regulating valves without tearing up the bathtub wall

Control the hot water temperature at faucets and showers that don't have anti-scald valves by installing either a mixing valve or a point-of-use tempering valve.

By the DIY experts of The Family Handyman Magazine

Two methods of controlling hot water temperature

If your home is plumbed with copper pipe, you can install a mixing valve right at the water heater and set the maximum temperature to 104 degrees F. You may still get some temperature variations due to fast changes in water pressure (such as from a toilet or a washing machine), but there will be no chance of scalding.

But before you break into any pipes or buy a water heater mixing valve, ask your local building inspector if your code requires “point-of-use” tempering valves at each faucet. These valves may be cheaper than installing temperature-regulating faucets.

Back to Top

Required Tools for this Project

Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.

  • Adjustable wrench
  • Rags
  • Soldering torch
  • Tube cutter

Required Materials for this Project

Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.

  • Copper pipe
  • Flux
  • Solder
  • Sanding cloth
  • Mixing valve with thermometer
  • Point-of-use tempering valve