How to Optimize Your Savings with a Water Heater Timer

Timing is everything, but is a water heater timer right for you?

Are you tired of wasting tons of energy running your water heater 24/7? Are you hoping to increase your home’s energy efficiency, but you don’t want to replace your unit just yet? If so, you might want to look into a water heater timer.

It’s not uncommon for the average household to leave their water heater on 24 hours a day to keep hot water ready at hand. Doing this, however, means your water heater can account for 18 percent of your home’s energy usage (1).

But before you shut down your laptop to go purchase a new unit, consider water heater timers.

What Are Water Heater Timers?

A water heater timer is a device that enables you to set your water heater to specific “ON”/“OFF” periods. So if you know you’ll be home at 5 pm, set the timer and your unit will operate accordingly. This trims down your energy bill, saving you some cash.

Water heater timers are available for both gas and electric-powered units. And although they require different fittings, the principal idea of automatically turning your unit on or off is the same.

How Efficient Are Modern/Old Water Heaters?

The efficiency of your water heater depends greatly on how old it is and how long it’s been in use. Water heaters have a tendency to decrease in efficiency as they age. Once they reach their 15th or 20th year of service, they need to be replaced.

The difference between old and modern units regarding efficiency comes down to regulations. The energy efficiency in all water heaters is indicated through the energy factor (EF) of the particular unit (2).

If we look at a conventional gas-powered, tank-type water heater, only about 50 percent of the fuel actually reaches the final point of supply. The rest is generally lost through standby losses, combustion, or distribution (3).

These standards have been updated to increase efficiency. Most modern models now include expensive efficiency-enhancing technology, but the downside is that this makes them more expensive.

Modern units are built in ways that reduce excessive heat loss. This automatically increases their efficiency since they need less energy when producing hot water.

Are Timers Worth It?

While a timer can’t increase your old unit’s energy factor, it can make your consumption more efficient. If you let your old water heater run all day, a lot of energy is wasted due to standby heat loss. In other words, you’re repeatedly heating unused water.

A water heater timer will prevent this from happening. As you set it to turn your unit off and on during specific times, less energy is wasted on reheating.

But, before you go to buy that timer, let’s go through some hard facts. While we may think our water heater runs 24/7, it actually spends most of its time in “standby mode.”

In fact, an older electric water heater may only be on for three hours a day (4). Newer models with higher efficiency ratings use a mere half of this time — some even using as little as half an hour.

Of course, this depends on the individual’s hot water habits. Large households will likely use more, whereas smaller homes use less. No doubt you can always increase your efficiency, but if you only currently run your water heater less than an hour a day, is it worth the trouble?

How Much Money Can They Save?

In the average home, a water heater accounts for around 18 percent of the utility bill (5). If you live in a larger household or don’t have an energy efficient unit, this number will likely be much higher. And unfortunately, a lot of this energy is lost to standby heat loss.

So if you’re looking into a timer primarily to save some cash, then you can’t go wrong. A normal water heater will fill its tank with cold water and proceed to heat it. The unused water will remain inside where it eventually loses heat.

Once the unit senses the declining temperature, it turns back on in order to restore the heat. This means that your unit continues to consume power even when you’re not home or using hot water.

A timer will prevent unnecessary usage by only activating the water heater according to your preset times. This will naturally save on your utility bills, but the amount depends on a few factors:

Some homes have found that their timer saved up to 25 percent annually on their water heating costs.

Take Note

To optimize your savings, we recommend that you consult a professional to get the most out of your timer.

Tips for Buying a Timer

If you want to buy a timer, there’s not much to consider other than the type and voltage.

Look for a device that’s compatible with the voltage of your water heater. For example, if your unit requires a 120-volt outlet, look for a timer that’s compatible with that.

The biggest factor to consider is probably which type. There’s a wide variety of water heater timers available for indoor and outdoor use. They range from the simplest On/Off switch to a high-tech device accessible through an app.

Each type has its own set of features and varying settings that you can choose from. Let’s have a closer look at some of the most common types.

1. Box Timers

Characterized by their box appearance, these timers are probably the most recognizable type. A box timer consists of either a digital control or a mechanical switch sitting in a confined box.

These are popular, easy to use, and reliable. You can set them exactly as you need, down to the hour and day for the coming week or month.

Box timers are generally recommended for households that have unaltered hot water schedules. They’re fairly easy to install and can cope with anything from 120 up to 270 volts.

2. Programmable/Digital Timers

Digital timers offer a bit more flexibility than box timers when it comes to added programmable settings. They’re a great fit for families who are eco- and budget-minded. They can be set at different settings for each day of the week — catering for changing hot water habits.

Digital timers generally come with a fitted LED control screen with backlight that’s very user-friendly. You can create preset times specifically modified to meet your own needs. For example, set one time for the weekends when you’re home all day, and another for the weekdays when you’re home less.

You mount them on a wall of your choice as they work remotely, however you’ll need additional wiring to connect them to your water heater. This, of course, means a professional should do the installation.

Some timers also allow you to connect it to your furnace or air conditioner unit. However, these are usually only for indoor use and will operate on a 110-volt outlet.

3. Countdown Timers

Countdown timers don’t offer as much flexibility as digital timers but are still useful. They work by counting down; for example, if you know you’ll need hot water in two hours, set it to a 60-minute countdown. After 60 minutes, it’ll start your water heater and you’ll have hot water for your shower.

Most countdown timers allow you to set them at preset intervals, generally ranging from 10 to 60 minutes. There’s not much high-tech involved with these. Some do offer a digital dial, but most have the usual mechanical dial.

You mount them on the wall, much like the programmable timers. They don’t have to be right next to your water heater but will need additional wiring. This means consulting a professional is a must for installation.

The main drawback of these is probably that they require some forethought, unlike the programmable timer you can set days in advance. With a countdown, you must plan for when you’ll need hot water and then set it manually every time.

4. Wi-Fi and Z-Wave Timers

Wi-Fi and Z-wave timers offer the convenience of smart technology, meaning you can control everything from your phone. These usually work in two ways. You can use them to set a specific time or simply as an On/Off switch.

While they do come with a heavier price tag than the ones above, you can use them to control several points around your home. This can include your garden lights, pool pumps, heaters, and of course, water heaters.

Most will include or recommend an app that you download to your phone, so you can control everything from a remote location. If you finish work early one day, simply connect to the timer through the app and turn on the unit so there’s water ready for you when you get home.

What’s more, most are made with durable material, allowing for outdoor installation. Some models even let you monitor your energy usage. This can help you increase your energy efficiency by giving you an overall view of your habits.

5. Gas Water Heater Timers

Most water heater timers are designed for electric units. But since gas-powered units generally rely on electricity to turn on and off, most timers will still work. You may even be able to find a Wi-Fi or Z-wave timer.

Still, be sure to consult a professional to check if your unit is compatible. Some gas-powered water heaters (usually older units) will need a special timer.

Check Before You Buy

Check how your water heater is wired before buying. Some units can only operate with a simple device such as a box timer.

How to Install a Timer

Installation of a timer will vary depending on timer type and your water heater. Some timers are a simple quick plug-in such as the box timers. Other types like the programmable and high-tech timers require a complete rewiring.

This involves disconnecting the wires entering the unit and connecting them to the timer. For this, we recommend that you consult a professional.

We’ll give you instructions on how to install a box timer — it’s pretty easy and straightforward, and you don’t need to be an experienced electrician. There should be an included manual with the device. If so, follow that and use our guide for additional support.

1. Shut off the Power

Before you touch any wires or electrical components, make sure that you shut the power off.

2. Select a Location

Select the best place to mount the timer. It should be in an accessible location, which also makes the installation easier. Place it so you can connect it to the water heater as well as the power source.

The best place would probably be a wall close to the water heater. Settle on a spot and secure it with screws.

3. Double Check Power

Before you proceed to the next step, we recommend double-checking that all the power is off. You can use a circuit tester to do this.

Remove the plate covering the power cable and check the wires for power. If there’s none, continue to the next step.

4. Connect the Timer

Disconnect the main electrical cord leading to the water heater. On the timer, there should be a hole for the electrical cord to go through, sometimes called the “knockout” hole. With a screwdriver or similar tool, give it a gentle bang to open it.

Pull the cord through and connect to the timer. Next, grab a new electrical cable and connect one end of that to the timer through the second knockout hole. The other end of this cable routes back and connects to the water heater. Make sure it’s the same size and gauge as the existing cable.

Tighten the cable grip screws around the cords and move to the next step.

5. Close and Turn On

Replace the plate on the water heater and timer. Then set the timer and turn the power back on.

Time Out

A water heater timer is a great investment for larger households with varied hot water habits. They can help save on the monthly energy bill by timing your unit’s operation to fit your needs. You simply set the time that you need hot water and it will automatically turn on your water heater.

However, they’re not for everyone. They might not be worth the trouble in smaller households with three or fewer people, for example.

Do you think a timer is for you? Let us know in the comments below how you save on those water heating bills.

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About the Author

Peter Gray

Peter has been a homeowner for 35+ years and has always done his own repair and improvement tasks. As a retired plumber, Peter now spends his time teaching others how they can fix leaks, replace faucets, and make home improvements on a budget.