If you want to buy a new hot water system but have no clue about the size, you’re not alone. If you keep running out of warm water at home or work, upgrading to the right-sized unit can make a big difference.
Buying the correct size is important because choosing something too small means it won’t keep up with your daily hot water needs. There are different sizes of hot water systems available, and tankless options are also available if you are short on space.
Tankless Water Heaters
Fitting a big water tank in a small apartment or unit can be difficult. For example, a 190-litre tank can take up a lot of room. In these cases, a tankless wall-hung system can be easier to work with.
These systems heat the water as it flows through, so you still get warm water to your taps and showers without the need for a large tank. They also come in a range of sizes, and some options are suitable for small bathrooms.
Water Heaters With Tanks
The size of the tank can be calculated depending on the number of people who will use it. For example:
A general guide is to add around 35 to 40 litres per extra person.
Most mid-sized families go for a 150-litre tank, which is usually affordable and suits most households, but you can always choose a different size based on your needs.
Calculating the first-house rating
Along with the capacity of the tank, you must also consider the water heater’s first-hour rating (FHR). This is the amount of hot water the tank can produce in 60 minutes and helps you understand how well it recovers during busy times.
To calculate the amount of warm water needed around the home, here are estimates based on a typical household:
are treated as higher-risk properties. Because of this, they must complete yearly testing to stay compliant, and some councils may require even more frequent checks.
Other things to consider
Some extra factors that can influence the size you choose include:
Conclusion
Choosing the right hot water system size mainly comes down to knowing how much hot water your household uses each day and what type of system suits your home. Once you understand your usage, the number of people in the home and the space available, it becomes easier to pick a size that works without wasting energy. If you’re unsure, a licensed plumber can assess your setup and point you in the right direction.