I find that showers and tubs are most relaxing when the water is kept at the right temperature, which is what is done when installing a mixing valve, which is important for new installations. Another thing I’d recommend installing any type of mixing vent duct unit (like my own) are anti-scald valves; these will protect you from burns from hot water mixing with cold water that cools too quickly!

Here are the steps on how to install a mixing valve on a water heater. Remember, if you are inconvenient or unsure about any of these steps, it is best to contact a professional.

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Prepare
Make sure the water heater control knob is turned to the “lead” position. Close the shut-off valve on the cold water line connected to the top of the tank. Next, turn on the hot and cold water faucets in the house to allow excess water in the pipes to drain. Now leave the heater for a few hours to let the tank and vents cool. You’ll know it’s ready when it feels cool to the touch.

To remove the heating vent tube from the top of the heater, first lift the flange on its bottom. Then push it and the lower end back to you to disconnect them.

Using an adjustable wrench, you can loosen the fitting on the upper end of the cold water pipe. Separate the accessories from each other and separate them (in opposite directions) before turning their original alignment upside down from each other – this will create enough space to safely insert your fingers between the wires without any struggle.

cold water connection
Wrap vinyl plumber’s tape around the threads below the shutoff valve, from where you separated the flex line.

Screw on the galvanized male and female coupler fittings and use a screwdriver to connect it back into place.
Install one end of the adjustable pipe wrench on the cold water pipe that is attached on top of this new connection; also, double check for loose parts, this will help prevent future connection errors due to other places in these pipes nearby or rupture and cause leakage!

Tighten all fittings by hand so that they are firm and there is no leakage in any direction when turning both handles left and right (clockwise).

You need to hold the mix valve with the knob facing up and align the cold water tee at the end of the shutoff valve. Pull off the blue cap from where it connects to the pipe before wrapping the tape around the threads. Holding the valve in one hand, screw the inlet onto the male end of the coupler. Use an adjustable wrench to tighten the mixing valve two turns clockwise.

Wrap vinyl tape around the threads on the bottom of the cold water tee and screw it into place by hand. Grasp the mixing valve with one arm while tightening its fitting with an adjustable wrench.

hot water connection
Use an adjustable wrench to loosen and remove the fitting on the upper end of the hot water hose from the line leading to your home. After this step, move it aside to continue.

Wrap vinyl tape around the threads of the hot water hose and attach the water heater hose to it. As an alternative, wrap the end with a pipe wrench as a backup.

To make this process easier, remove the red cap from the bottom of the mixing valve.

Next, wrap vinyl tape around the threads and use an adjustable wrench to attach a 12″ flex wire to the bottom.

Pull the red plastic cap off the lower end of the hot water tee on the valve. Wrap vinyl tape around the threads. Use an adjustable wrench to attach the upper end of the original flexible pipe that was detached from the hot water pipe to the hot water tee.

Slowly open the shut-off valve at the cold water line. Now check all connections for drips and make sure there are no leaks. If necessary, tighten the connection to stop dripping.

Fix the exhaust pipe back into place. Set the water heater control to medium temperature and let the water in the tank heat for about an hour. Please review the installation instructions before adjusting the temperature of the mixing valve and water heater.

enjoy warm water
A quick recap of the steps to install a mixer on a water heater: First, turn off the power to the water heater. Next, remove all insulation around the old valve and unscrew it from the top of the tank. Once this is done, slide the old stem assembly out and properly discard or recycle if necessary. Keep your workplace organized and avoid missing parts!

Now install the new stems, placing them in the holes in the bottom of the tank in the correct order so that they stand vertically (stem A on top). Use an adjustable wrench to screw them into place with some teflon tape until it’s tight enough that each part can’t be more than 1/4 inch apart when pressed together. Finally, screw on all three valves tightly and enjoy the warm water!