How To Install a Hot Water Regulator

Updated: Jan. 24, 2024

Install temperature regulating valves without tearing up the bathtub wall.

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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.

Tools Required

  • Adjustable wrench
  • Rags
  • Soldering torch
  • Tube cutter

Materials Required

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

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.

Project step-by-step (3)

Step 1

Water heating mixing valve

Cut the copper pipes at your water heater and reroute them through a mixing valve. Install a temperature gauge in a tee fitting near the valve to set the output temperature.

How To Install A Hot Water Regulator Water Heating Mixing ValveTMB STUDIO

Step 2

Tempering valve

Install a “point-of-use” tempering valve below the sink. Shut off the supply valves and disconnect the existing supply tubes. Add the tempering valve and two new supply tubes.

How To Install A Hot Water Regulator Tempering ValveTMB STUDIO

Step 3


Turn on the hot water and adjust the tempering valve to obtain 104 degrees F. or less.

Hot Water Regulator Close UpTMB STUDIO