What Size Hot Water Heater Do I Need?

Hot water heaters consume a lot of electricity and can significantly raise your electricity bills. And that could, in turn, burn a hole in your pocket!

That is why you need to purchase the right-sized water heater, which will fit your needs well and help conserve electricity. Having said that, we know that it is not easy to make a choice as there are various sizes available and a hoard of factors to consider before purchasing.

To make it easier, we have curated this detailed and comprehensive guide about all the factors that have to be considered beforehand. This will help in making the right choice, thereby enabling you to save on your utility bills.

So, what are you waiting for? Grab a cup of coffee and dive in!

What Size Hot Water Heater Would You Need?

The size of a heater and the tank is directly related to the number of showerheads and appliances that you have in your house. On that note, here are the things to keep in mind:

Size Of Water Heater

When it comes to instant hot water heaters, you will need a ≥7L per 60 seconds unit if you have a single showerhead. But if there are 2 showerheads, then a ≥14L per 60 seconds option will be better.

Moving on, for large houses with 3 showerheads, you will need a ≥21L per 60 seconds unit. And for 4 showerheads, a ≥28L will work well. It is essential to pay attention to the measurements as otherwise, you may have to wait for quite some time for the water to get heated.

For example, if there is a family of 5 people, there will be an average of 3 shower heads, which means you will likely require ≥21L per 60 seconds unit.

The size of the hot water tank has to be between 60 and 80 gallons. Here, we are assuming that 3 showerheads will be running at the same time but if that is not the case, you can settle for a smaller tank too.

Size Of The Water Heater Tank

The second most important thing to consider is the size of a heater tank. If you live alone, then you will need 30-40 gallons or 115 to 150 litres tanks. But for 2-3 people, you will require a tank with a capacity of at least 40 to 60 gallons.

If there are 3-4 people in the house, then you may settle for a capacity of 50 to 60 gallons. And for a family of 5 people, a total of 60 to 80 gallons will ideally suit your needs.

Guide To Hot Water System

One of the significant determinants of a hot water system is the number of showerheads and their type. You might have a water-saving showerhead or a standard one, and the water requirement will vary according to that. So, read on to know more about this.

How Much Hot Water Does A Shower Use?

The first consideration is the number of showers that will be working simultaneously at any given time. Since these are instant water heaters, if one showerhead is switched on at one time, you can opt for a smaller tank of 30 to 40 gallons even if there are 4 members in the house. So, in this case, what matters here is the number of showers that will work simultaneously.

Moving on to the approximate rates, if you are going to use 2 shower heads at the same time, a 16L/minute hot water heater will be required. Similarly, for 3 heads, you will need a 24L/minute water heater, and for 4 heads, a 32L/minute model will be your best bet.

However, you need to know that the calculations are made keeping in mind the 3-star water-saving ratings of showerheads, which are attached to an instant gas water heater. And if you are planning to use washing machines that need hot water, the number of showers that can function simultaneously will go down.

Determining Factors

There are some determining questions that you need to ask yourself before making a purchase decision, namely:

• Do all the family members shower at the same time in a day?
• How many bathrooms with showerheads do you have?
• Does your shower have a 3-star water-saving rating?
• Does the washing machine run at the same time as any of your showers?
• How much hot water do you prefer while bathing?
• Do you have a spa or a bathtub that requires a lot of hot water?
• Is your dishwasher connected to cold or hot water?
• Do you live in an area with a cold climate?

Now the number of showers that work simultaneously will help you determine the size of the water heater. Also, as we have already mentioned, the washing machine and dishwasher play a crucial role. If they need hot water at the same time as the showers, then a bigger tank will be necessary.

In addition to this, if you live in an area with a cold climate, then more hot water will be needed as compared to living in hot weather. So, carefully answer all the above questions to figure out the right size of the required water heater.

Apart from that, in order to calculate the size of the system, you will need to compare the capacity of continuous flow with its peak usage rate. There are water-saving showerheads available on the market, and those are the best choices to make.

To find the right capacity, just multiply the flow rate of your shower by the average number and length of showers at any given point of time.

Tankless Systems

With tankless systems that are generally powered by natural Gas or LPG, you will receive a continuous flow of hot water. Again, the size of the unit would depend on the number of showers and machines that are running simultaneously.

For example, if 2 showers are switched on at the same time, then the device has to function with a minimum flow rate of 14L/minute. And if there are 3 of them, then the rate needs to be at least 21 L/minute. Likewise, if you plan to use any other hot water appliance, then count that as a single unit and then measure the capacity.

Things To Remember

Buying The Right Size

When it comes to hot water heaters, you must already know that they consume a lot of electricity, and you would not want to overspend on them. For that, you need to purchase the right size as a bigger option will consume more electricity. Larger ones need more heat owing to their large capacity, which means more water will need to be heated at a time.

This will, in turn, increase the operating costs and then the overall expenditure. Hence, count the appliances that need hot water and then proceed to decide the size.

Shower Time

Showers consume the most amount of hot water, and hence the time you spend bathing is very important in making a decision. Now, an average person spends 5 to 10 minutes in the shower, and one mixes hot and cold water to achieve the perfect temperature. Keeping that in mind, the average consumption would be somewhere near 7L/minute.

So, if you shower for 8 minutes, then 56 litres of hot water would be needed for bathing once. In that sense, if you have 5 showers switched on simultaneously, you will need around 280 litres of water.

Hence, if you have a bigger family, make sure that you use WELS (Water Efficiency Labelling and Standards) 3-star shower heads that will help save energy and water. Water shortage is becoming a major issue all around the world, and this needs to be taken into consideration.

What Is The Preferred Shower Temperature?

The average temperature that people are comfortable with is 38 to 42 degrees celsius. But the temperature of the water released by most water heaters is about 50 degrees celsius, after which you may mix it with cold water to strike the right balance between hot and cold.

The Perfect Size Water Heater

Once you have the right-sized water heater in the house, every person can take a bath comfortably without compromising on hot water. We would again remind you to take into consideration all other appliances that need hot water simultaneously and then calculate the size.

Also, calculations will be different for a hot climate and cold climate as the need for hot water in hot weather will invariably be low. However, in a cold area, you might want to get a hot water supply in the kitchen too.

Let us know about any further queries in the comment section below.

Until next time!