Last Updated: Sep 10, 2021
Heating the water we use for showering, washing dishes, and washing the clothes is the second-highest energy use in most American homes. Around 14 percent of all energy that we use comes from heating (and storing) water. Most water heaters will run for approximately three hours per day. However, that number can increase significantly in homes with high water demand. Older water heating storage tanks and those not adequately insulated will also lead to higher water heating energy expenses. A straightforward way to reduce your residential energy usage from your hot water demand is by installing a water heater timer. Below, we offer a complete rundown of how these devices work and how much you can potentially save.
Before going on an extended vacation, many homeowners might turn off or turn down their water heater before leaving. Why waste energy and money heating water that you are not going to use while touring the world? But what about the 8-10 hours during the day when the entire family is either at work or school? Or the 8 hours at night when everyone is sleeping?
Water heater timers essentially allow homeowners to determine when their water heaters will function, depending on the times of the day when the occupants require hot water. These devices work best for households with relatively stable schedules and when the house is unoccupied for long periods. A family of four where both parents work standard 9 am to 5 pm jobs, and both children are in school from 8 am to 4 pm would stand to benefit from installing a water heater timer.
Water heater timers are programmable devices, like programmable thermostats, but for your household water supply. They allow homeowners to control when the water heater is functioning without having to crawl into the unfinished basement to turn your water heater off and on. Homeowners can program the timer so that hot water is available only during the times of the day when it is most required.
Water heater timers are incredibly easy to install. Homeowners with a bit of DIY prowess can re-route the main power cable from the water heater through the water heater timer. A new cable is then connected from the timer casing to the water heater. Most water heater timers have small dials that allow you to program when the heater turns on and off.
When turned off, water heaters generally take between 30 and 45 minutes to heat the water in the storage tank. Once heated, that water will stay hot for anywhere between 3 to 6 hours, depending on how well-insulated your storage tank is. Wrapping a simple batt insulation blanket around an older water heater is one way to improve the insulation performance without investing in a new heater.
A family of four might program the water heater to turn on around 4:30 pm to get hot water ready for use when they return home from work. The heater would run for about 30 minutes before turning off. The family would have a steady supply of hot water from 5 pm until 10 pm for showering, washing dishes, etc. The timer could then be turned off at 10 pm when people went to bed and programmed to start up again around 6 am. Another 30-minute heating cycle would give the family hot water for morning showering and cooking before, again, turning off the heater around 8:30 am when the house is left empty for the day.
In this example, the water heater would only run for about one hour each day (30 minutes in the afternoon and 30 minutes in the early morning). The average water heater uses around 4,000 watts of energy, though more efficient models are available on the market. A 4,000-watt water heater used an average of one hour per day would use 4 kWh per day, for about a $12 monthly cost, or $146 per year (assuming a $0.10 per kWh electricity cost).
That same water heater without a timer would run for at least three hours per day, perhaps more, if the storage tank were not well-insulated. The water heater would use 12 kWh per day at three hours per day for a $36.50 monthly cost, or $438 yearly cost.
In one year, then, merely installing a water heater timer could save the family of four $292 each year. Water heater timers are relatively inexpensive devices, costing about $50 on Amazon. Even if you have to pay a $150 labor fee for professional installation, water heater timers can quickly pay for themselves in under one year.
“Average Savings: $292 Annually!”
Water heater timers are a simple and effective way to put a dent in your household energy bill while also cutting back on your carbon footprint. For homeowners who want to go a step further, however, you might consider moving on from tank-style heaters altogether.
On-demand water heaters do not require any storage tank and can easily save you upwards of $100 each year on water heating. In most areas of the country, solar water heaters are also an option. They can effectively reduce your carbon footprint from heating water to zero.
A drain water heat recovery system is a great option to maximize the sustainability of any hot water heating system. It "rescues" the heat in the water that goes down your sink and shower drain and recirculates that heat to your piping system. In many cases, drain water heat recovery systems can reduce your water heating bills by up to 40 percent!
Another option that gives homeowners more control over their water heating is to install a programmable, smart thermostat to your water heater. Aquanta is one such device that essentially acts as a smart thermostat for your water heater that you can control from your smartphone.
No, there is no reason to continually heat water when no one is going to use it. Water heating timers allow homeowners to control when hot water is available, depending on their daily schedules and their requirements for hot water.
Yes, in most cases, you will begin to see savings on your first monthly utility bill. Most households can expect to save around $300 per year once they install a water heater timer.
Yes. Even if you wake up at midnight and want a hot shower to relax, turning on your water heater will give you a supply of hot water in only 30 minutes.
Most water heaters run for an average of three hours each day. However, older models and storage tanks with inadequate insulation will run for much longer.
Yes, and this is a common practice for many homeowners. Water heater timers essentially allow you to do the same thing daily.
Turning off your water heater will reduce energy consumption to zero during the hours when it is not in operation.
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.