How to adjust temperature on electric hot water heater

Q: How do I make my electric water heater hotter?

Locate and remove the thermostats access panel. Pull back the insulation. Adjust the thermostats temperature setting using a flathead screwdriver. If your heater has two thermostats, both need to be adjusted the same amount, with the top thermostat set a few degrees higher than the bottom thermostat.

Table of Contents Show

How to adjust the temperature on a water heater.
Check list:
How do I make my electric water heater hotter?
What should my hot water tank thermostat be set at?
How do I control the temperature on my hot water heater?

Anna Maria Beach on a Bad Day.

Living in Florida, one could say we only have two seasons, Summer and Winter. Those are the two seasons when the temperature changes enough that I change the the thermostat on the water heater. You see in the summer we don’t need the water to be as hot because the ground is warm. In the winter… or what we call winter, the ground is colder so the water is colder and it takes hotter water to make it comfortable for things like showering. Otherwise, in the winter, you are using more hot water and lets face it when you have a family or house full of holiday guests… you can run out of hot water quickly.

How to adjust the temperature on a water heater.

Check list:

Anatomy of a water heater

Tools- You need a couple of screw drivers to adjust the temperature control. A #2 Phillips (medium size head) to remove the cover and a small standard (flat) blade screw driver to adjust the thermostat. You will also need a candy thermometer or similar to test the actual water temperature.

Parts required-None

Time- 15 – 20 minutes to set plus time for the water temperature to stabilize.

Skill level – Amateur/Beginner

Cautions: Never touch a wet water heater until the power is off, be sure the power is off before repairing an electric appliance.

Steps:

Step 1: Find the electrical circuit breaker, electric disconnect or fuse that supplies power to the water heater.

Most newer homes will have a disconnect within eyesight of the water heater. It may even be as simple as a heavy duty light switch.

If you have an older home look for a circuit breaker and switch it to the off position, a disconnect, pull it out, or if a fuse, unscrew it. If the source is not labeled or you have any doubt, turn off the main circuit breaker or pull out the main fuse to shut all the power off. Remember, we don’t need to be macho, better safe than sorry.

Step 2: Remove the thermostat cover panel.

Using the Phillips screw driver, remove the two screws that hold the cover panel in place and set them aside. Remove the cover panel and block of insulation behind it that will be covering the thermostat and set these aside. On larger water heaters there are normally two panels one above the other. You will need to access both thermostats.

Step 2: Locate the small adjustment screw.

Thermostats

Once you remove the cover you will find that each thermostat has a small screw with an arrow or other type of indicator showing where the temperature is set. This is usually toward the bottom of the thermostat. Some are labeled with the temperature settings in degrees, others may be labeled Hi and Lo or Hot A B C and Very Hot. On the Hi Lo the Hi setting will usually be 140° and the Lo setting will be some where around 90°. The one labeled with Hot A B C Very Hot, the hot setting will be around 120°, setting A will be 130°, B 140°, C 150° and Very Hot 160°.

Step 3: Setting the temperature.

Using the flat blade screw driver turn the

screw clockwise to increase the temperature or counter clockwise to decrease the temperature. Use slight adjustments until the arrow or indicator points to the desired temperature. Recommended settings are between 120 and 140 degrees. These settings are approximate. Be sure to set both thermostats to approximately the same temperature.

Step 4: Re-install the cover/s

Be sure to properly re-install the insulation block and secure the covers. Leaving the insulation and covers off can cause cool air to interfere with the proper operation of the thermostat.

Step 5: Re-set the Electric

Turn back on the circuit beaker, re-insert the disconnect or screw in the fuse. Run the hot water for several minutes to lower the water temperature in the heater and then allow sufficient time for the heater to adjust to the new temperature before proceeding to step six.

Step 6: Test the temperature

Use caution when using the hot water until you have determined the temperature. Remember, water that is to hot can scald small children and elderly adults. Using a candy thermometer or similar, test the temperature of the water by either holding the thermometer under hot running water, or filling a large cup with hot water to place the thermometer in. Keep the thermometer in place until the temperature stops raising. This will be a more accurate reading then the setting on the thermostat. If the temperature is not where you expect it to be, follow these steps again to re-adjust the thermostat until you are satisfied with the temperature.

How do I make my electric water heater hotter?

Locate and remove the thermostat's access panel. Pull back the insulation. Adjust the thermostat's temperature setting using a flathead screwdriver. If your heater has two thermostats, both need to be adjusted the same amount, with the top thermostat set a few degrees higher than the bottom thermostat.

What should my hot water tank thermostat be set at?

A domestic hot water cylinder thermostat should be set at 60-65ºC. This is high enough to kill off harmful bacteria such as Legionella. If you set the thermostat much higher than this the water that comes out of the taps will be too hot and there'll be a risk of scalding.

How do I control the temperature on my hot water heater?

Twist the dial on the bottom of the water heater to change the temperature. Gas water heaters are easy—they feature a single knob that controls the amount of heat being directed to the unit. Turning this knob to the left (counterclockwise) will crank up the temperature, making the water hotter.