Water heater safety is rarely something you think about. In fact, most people don't think about their water heater at all. It's an easy appliance to take for granted. It sits in a closet, in your garage, or somewhere else out of site in your home and quietly does it's job.
If you don't regularly maintain your water heater, then it shouldn't a surprise when something goes wrong out of the blue. In fact, the average homeowner only remembers it's existence when they suddenly realize they don't have any hot water . . . or worse, they find their water heater sitting in a puddle of water!
All water heaters require regular maintenance and traditional tank-style units are no different. In fact, beyond preventing leaks, the failure check the Temperature and Pressure Relief Valve (T&P Valve) could cause serious injuries and damage to your home.
How to Check Your Water Temperature
Many water heater manufacturers use vague settings on their Temperature Control knob such as Warm, Hot, and Very Hot. Frequently the factory temperature default setting is 140°F, but it can also vary among manufacturers.
It's a good idea to test the water temperature at the faucet. As a general rule, the temperature should be at least 120°F. Scalding can occur at 130°F, but most likely your reflexes kick-in and you'll pull your hand away before you experience any burns.
Here's what to do:
- Allow the hot water to run for 3-minutes at the faucet nearest the water heater.
- Fill a drinking glass full of hot water from the faucet.
- Test the temperature of the water with a cooking thermometer.
- The recommended temperature is 120°F (Consumer Product Safety Commission).
- Adjust the temperature setting up or down as needed.
- Wait 3-hours before testing again to allow for changes to take place.
For many years the standard temperature has been 140°F and this temperature is still often used as the default setting by water heater manufacturers.
But there are a few things you should know regarding water heater safety before making any adjustments to your hot water temperature.
If the water temperature is below 120°F there is a risk of contracting legionnaires disease. The legionella bacteria can grow at temperatures below 120°F and can be contracted from the water mist when taking a shower.
If you do have low water temperature, it might be a sign that your dip tube needs replacing.
Legionnaires' disease is a severe form of pneumonia. It can be contracted in areas such as the shower where microscopic water droplets are inhaled. The risk of colonization of Legionnaire bacteria is significant in hot water tanks where the temperature is between 104° and 122°F.
According to the Mayo Clinic there is a possibility of contracting Legionnaires disease from home plumbing systems. However, most outbreaks take place in large buildings such as hotels or apartments. One reason for this may be because large buildings have very complex plumbing systems where the bacteria can easily grow and spread.
At a temperature above 130° there will be an increased amount of sediment build-up within the tank as well as wasted energy. There is also the health risk of scalding.
When the water temperature is at 140°F there is a serious risk of receiving a 3rd degree burn.
A 3rd-degree burn involves all the layers of the skin and it is the most dangerous of all the burns. These burns can occur in adults within 6 seconds at a temperature of 140°F. Elderly and young children can experience 3rd-degree burns in just a single second!
Did you know that there have been incidents where a home has seen devastating damage because a tank-style water heater exploded?
Although the T&P Valve is designed to prevent this from happening, if the valve isn't tested on a regular basis your water heater could burst with enough force to cause disastrous consequences to your home.
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When the water within the tank of a water heater reaches an excessive temperature it can cause the tank to explode. A tank that is showing signs of internal corrosion can also factor into the situation.
If the temperature of the water within the tank is below 212 degrees, the main concern is scalding and severe burns. However, if the water temperature rises above 212 degrees the water will turn into steam.
Steam takes up 1,700 times more space than water, which increases the pressure within the tank to a point where it must be relieved or it could explode. If the T&P Valve does not properly activate, the water heater tank can burst.
CAUTION: If you ever turn on your faucet and have steam instead of hot water and/or your T&P Valve is releasing steam or water, immediately SHUT OFF the fuel source to your hot water heater.
If your water heater is electric, turn off the circuit breaker. If it is gas, close the gas valve. Then call a professional plumber.
- NEVER try to relieve the pressure yourself. Stay far away from the water heater!
- NEVER add cool water to the tank or spray the tank with a hose.
- ALWAYS allow the water heater to cool naturally.
Hot water heaters are an important appliance within the home, and by taking a few precautions, you'll be able to keep your home safe from many unforeseen dangers.
- Gas water heaters installed in a garage should be raised so that their pilot light is 18" above the floor.
- Use caution when using flammable liquids or aerosol bug bombs when you have a gas water heater. Always extinguish the pilot light first.
- Secure your hot water heater with earthquake straps, even if they are not required in your area.
- When insulating pipe wrap is used on a gas water heater, be sure that its not within 6-inches of the flue exhaust or draft hood.
- The vent system should be the same diameter as the water heater's draft diverter. It should not have any dips and go straight up and outside.
- Keep dust, paper and other combustibles away from your water heater.
- Install an automatic gas shutoff valve to stop the flow of gas in case there's ever a dramatic increase in gas pressure or an earthquake.
- Install a carbon monoxide detector within 15 to 20 feet from your gas powered water heater.