Water heater temperature setting a b c

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 If you have already set the temperature and are saying to yourself, “I have no hot water” or not enough of it, there are a few factors that may be affecting the heat. If all else fails, the heating element may be failing, and needs to be replaced.

How To Check Your Water Heater Temperature

Most water heaters do not have a temperature gauge with a readout. Instead, the thermostat is marked with temperatures or heating ranges. To accurately find the hot water heater temperature, you will need a cup and a cooking thermometer.

Allow the water heater to sit for a minimum of one hour without using it, and then turn on the faucet closest to the water heater. Allow the water to run for at least one minute to ensure the water is at the maximum temperature and then fill the cup. Insert your cooking thermometer, and then adjust the settings as desired.

Water heater temperature setting a b c

Water heaters are factory set at OSHA recommended levels, around 140 degrees. On the other hand, the EPA suggests turning the thermostat down to 120 to reduce power consumption, and a booster heater to reach sanitizing temperatures at select outlets.

From another point of view, lower temperatures are better for households with small children, while higher temperatures are more efficient at cleaning and sanitizing.

My Recommendation

Personally, I believe a water heater should be set to 130 degrees in almost all cases. It's low enough to prevent scalding yet hot enough to kill off harmful bacteria.

How To Turn Up Your Water Heater

You can adjust hot water heater settings to get more hot water if you are unhappy with the recommended temperature. Hot water heater settings are easy to adjust, although electric heaters will require a screwdriver and possibly a small wrench or socket.

Keep in mind that the thermostat is factory preset to a recommended temperature and changing the setting may increase the potential for serious burns.

How to Set Temperature on a Gas Water Heater

Gas water heaters have a setting knob that can be turned to adjust the temperature. Most gas control valves have a knob with various labels such as A-B-C on them. Different brands of gas water heater control valves may have different labels. In most cases, here’s what each label means:

  • Low (or Warm) = 80-90°
  • Hot (or triangle symbol) = 120°
  • A = 130°
  • B = 140°
  • C = 150°
  • Very Hot = 160°

Sometimes there is a “Vacation” setting. This does not heat water, but keeps the pilot light ignited.

How to Set Temperature on an Electric Water Heater

Turn off the circuit breaker. Remove the access panels. Locate the thermostat adjustment beneath the insulation. Using a straight screwdriver, adjust the thermostat control towards the desired temperature. Replace the insulation and panels, then restore power. Here’s a good video showing the process:

Factors That Affect Water Temperature

Some factors that may affect your hot water temperature are the distance from the water heater to the outlet, how the pipes are installed, and the condition of the heating element itself.

Small bore pipes and long distances will require longer times for the hot water to reach the opening, for example, and pipes that run beneath or outside the home may be subject to winter or summer conditions.

If you have a large house, you may want to look into installing a hot water recirculation system which can mean less time to get hot water in all outlets of the house and well as substantial cost savings over time.

If adjusting the thermostat still doesn’t give you the right temperature, it may be time to replace the water heater element. If you don’t notice a difference in water temperature after adjusting the thermostat, it’s also possible you may have a faulty thermostat that needs replacing.

What does AB and C mean on a hot water heater?

Here is what temperature each letter stands for: Hot- 120 degrees. A- 130 degrees. B- 140 degrees. C- 150 degrees.

What setting should my water heater be on?

Professionals recommend keeping your water heater set at a temperature between 130 and 140 degrees Fahrenheit. Any higher, or lower, could actually be dangerous for you and your family. While turning the temperature up higher can result in burns, turning it lower than the recommended setting can also be dangerous.

Which thermostat should be set higher on a water heater?

Peel back the insulation. Use a flathead screwdriver to adjust the thermostat up or down. If your water heater has two thermostats, adjust both the same amount. The top thermostat should be a few degrees higher than the bottom.