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What Hot Water System Size Do I Need?

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The right hot water system size is important to know so the best system can be installed. Knowing the heating capacity needed, if the heater is continuous or storage to how much hot water is usually used will influence what size hot water heater is needed. When choosing the best tank to install, looking at its size and volume are the main components to look for. Here at Optimised Plumbing Services, we offer trusted hot water system repairs and installation services where we can offer advice on the best size tank to install.

The hot water system size will be influenced by the type and model of the hot water system. For a storage hot water system looking at the capacity and volume of the storage tank is needed. For continuous flow systems, the flow rate needs to be considered. Solar hot water systems will need more or larger panels the greater the hot water demand is. When looking at electric natural gas and electric hot water systems the number of people and hot water outlets need to be considered for the size of the system.

What Hot Water System Size Do I Need for a Storage Tank System?

When deciding on what sized storage tank to be used in the hot water system, looking for the volume and capacity of the tank is needed. Larger storage tanks mean that there needs more energy to heat the water. This often leads to enhancements being added, such as insulation, to have the element or burner not work as hard. Smaller systems will also not always take less energy to heat water as higher energy efficient models mean less energy is required.

The volume of the tank also does not have to be the exact same as how much water it can deliver. Estimating per person 30-40L for a gas system and 50-60L for an electric system will help influence what size hot water storage tank is needed for the home. 

What Hot Water System Size Do I Need for a Continuous Tank System?

When deciding on the size of the tank for a continuous hot water system the flow rate is what needs to be considered. Knowing the flow rate is important to know how many water outlets can receive hot water at once. The flow rate can be calculated by thinking of how many water outlets might be used at one time. Understanding the litres per minute often used during peak demand times around the home can be useful.

What Hot Water System Size Do I Need for Solar, Electric and Gas Powered Systems?

For a guide on what hot water system size to be used for the main types of hot water systems, read below:

Solar Hot Water Systems

Number of PeopleHot Water Needed (L)Approx. Tank SizeCollector Area (m2)

Electric Hot Water Systems

Peak RatesOff-Peak Rates
Number of PeopleCapacity (L)Number of PeopleCapacity (L)

Gas Hot Water Systems

Tank StorageContinuous Flow
Number of PeopleCapacity (L)Number of Outlets usedFlow Rate (Litres per Minute) 

To know more about the different types of hot water systems, including what heat pumps are, we recommended reading our blog for more information. 

Professional Hot Water Repairs and Installation Services

Optimised Plumbing Services offer the best hot water repair and emergency hot water services in Sydney. Our fully qualified plumbers are here to perform repairs, installations and hot water system replacement work at any time of the day. Our experienced plumbers are also here to provide useful advice on the recommended hot water system size

We offer our hot water services, as well as our Blocked Drain and Emergency Plumber services, to all of Sydney, including North Shore and Inner West. For the best hot water system repairs, installations and replacement work – always rely on Optimised Plumbing Services!

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