If you keep your water at a high temperature all the time, you will lose more heat to the environment even if the cylinder is well insulated. Your water
It depends on how much hot water you are using and when. It can be more economic to keep it on constant. It takes longer to heat a full tank of cold water than it does to heat the water as it's used. If it's on constant then it'll not fire up unless it needs to. 'Constant' is a bit of a misleading term.
Here's the catch: Modern water heaters are well-insulated meaning there is very little heat loss. Although electrical rates vary, the experts say turning off the water heater at night will likely save about two dollars a month.
The price of electricity is about three times the price of gas or oil. It's generally much cheaper to heat water using your central heating system, rather than using electricity with an immersion.
Only heat the hot water twice a day
Try heating the water for an hour in the morning and an hour in the evening. Start the water heating about an hour before you need it. For example, if you shower at 08:30, start heating the water at 07:30. If you wash up in the evening at 19:30, then start the water heating at 18:30.
Timers are most cost effective if you don't want to install a heat trap and insulate your water heater tank and pipes. Timers aren't as cost effective or useful on gas water heaters because of their pilot lights.
If you have a hot water cylinder, then hot water stays hot for hours if not days if it isn't used. Invest in a timer to heat the water only when it's most frequently used – typically in the morning and evening when people are most likely to take baths or showers, and you need to wash up.
Water heating is the second largest energy expense in your home, accounting for about 18% of your utility bill. To conserve hot water, you can fix leaks, install low-flow fixtures, insulate accessible hot water lines, and purchase an ENERGY STAR certified dishwasher and clothes washer.
However, the Department of Energy notes that turning your water heater temperature down to 120 degrees Fahrenheit can help save energy.
Usage Patterns: If you frequently use hot water late at night or early in the morning, it might be more convenient to leave the tap on. This ensures that you have instant access to boiling water when you need it. However, if you rarely use hot water during these hours, turning the tap off can save energy.
- For a storage water heater, it is sufficient to switch it on for 10-30 minutes before showering. - Leaving a storage water heater switched on for the entire day may cost you an additional $124 a year*.
Turning your water heater off completely when it's not in use can help you save a small amount of money each month on your energy bills, but the hassle of manually turning your unit off and on typically outweighs the benefits.
Although it takes longer and requires more fuel to heat cold water, the energy required to maintain this constant temperature is much more expensive than the few times it is heated when necessary on occasion, due to its non-use, this water is also wasted, as a result, running a boiler continuously consumes more fuel ...
The recommended setting for this control is 60°C/140°F. (Storing hot water at temperatures of less than 55°C is not advisable due to potential for Legionnaires disease). If the water coming out of your taps is too hot then check this control as it could be set too high.
Typically, a hot water heater that uses a tank will run for 3 to 5 hours per day. So, a 4,000-watt heater used for 3 hours a day at 10¢ per kWh will cost $1.20 per day, about $36.50 per month, or $438 per year.
Put simply, heating your water via your central heating gas boiler is your cheapest and most efficient option, if you have it. Of course, many people don't have gas, so it is not always an option.
Set too high, or at 140ºF, your water heater can waste anywhere from $36 to $61 annually in standby heat losses. Additional savings will be realized by the lower temperature for consumption (from water demand or use in your home, such as clothes washing, showers, and dishwashing). These may amount to more than $400.
C - 150° F - About 1-1/2 seconds. B - 140° F - Less than 5 seconds. A - 130° F - About 30 seconds. HOT - 120° F - More than 5 minutes. LOW - 80° F - No hazard.
The maximum Department of Energy recommended water heater temperature setting you should never exceed is 140 degrees Fahrenheit. The lowest recommended setting should never be below 120 degrees Fahrenheit.
Why turn off your water heater? Turning off your water heater, like many other electrical appliances, can save you money each month on your bill. A small amount of heat escapes when the water heater is turned on, even though it's well insulated. Typically, this loss of energy is about 10 percent of your bill.
It's better to leave the hot water heater on all the time, rather than turning it on and off. This is a very common energy saving myth. But in fact, you really don't need to be heating your water all the time. Your immersion heater or boiler will heat up hot water which is stored in a tank.
Water Heater Temperature Recommendations
120 degrees Fahrenheit is the safety recommendation against scalding, but 140° is the common default setting.