If you’re trying to work out what size hot water system to buy, you’re probably hoping for a quick answer like “2 people = this size” or “4 people = that size”. But it’s not that simple. Headcount gives you a good starting point, but what really matters is how your home uses hot water at its busiest times.  Two people taking long, back-to-back showers can easily use more hot water than a family of four who take shorter showers and space out their usage instead of running everything at once. That’s why sizing is not just about numbers but also about your routine and a bunch of other things we’ll walk you through in this guide. It’ll help you choose a system that actually works for your home without running out or being oversized. TL;DR How Hot Water System Sizing Differs (By System Type) Storage Systems Storage systems heat water and keep it in a tank, so these systems are sized in litres (L) and come in a wide range of sizes – from small 25L units for single-point use (like a single tap) to large 400L+ systems designed for full family homes. The number tells you how much hot water is available in storage at one time before the system needs to recover. Continuous Flow Systems (Instantaneous Systems) In continuous flow systems, since there is no tank and the system heats water as it passes through the unit, they can’t be sized based on a litre capacity; instead, they are sized by flow rate in litres per minute (L/min).  Continuous flow systems usually range from 12 L/min to 32 L/min+. This number shows how much hot water the system can deliver at one time, which determines how many showers or taps can run together without losing temperature or pressure. Now that you understand how sizing works differently for each system, you can apply the right method to the system you’re installing in your home and work out the correct size from there.  The Main Factors That Determine What Size Hot Water System You Need Number of People In The Household The number of people living in your home is the starting point for understanding your hot water use, as more people means more showers, dishwashing, laundry, etc., which all add up quickly. In Australia, one person uses about 50 litres of hot water per day. Based on this per-person usage and the number of people in your house, you can calculate your family usage and the size of your storage tank.  For instance, if you have a family of four, 4 people × 50 L each = 200 litres of hot water usage. Now, since your family uses around 200 litres a day, it might seem logical to go for a 200L tank, but please don’t. Because, for instance, in real life, someone might take a longer shower, or there might be an extra load of laundry to do, which can increase your family’s usage from the calculated value and empty the tank earlier. That’s why you always add a buffer of around 50–100 litres, so you don’t run out of hot water.  For a continuous flow system, the number of people doesn’t directly decide the size because it heats water as you use it, not based on how much is used overall in a day. But it still helps you understand the overall system size. For instance, more people mean a higher chance of multiple showers or taps running at the same time, which pushes you towards a higher flow rate system. Peak-Time Hot Water Usage Peak time is the busiest hour in your day – usually the morning before school or work, or the evening after sports and daily routines – when most hot water is being used at the same time. In a storage system, the tank needs to hold enough hot water to cover everything used during this peak window.  To calculate this peak usage, look only at your busiest 60 minutes and add them up. Now imagine most of this happening in the same hour. For example, in a typical family morning: That already puts you at around 200+ litres in one peak hour, without even adding anything extra like taking longer showers. So, for extra usage, step up to a safe working range by choosing a tank size 20–30% larger than the calculated peak demand.  If you are sizing a continuous flow system, you need to find the litres per minute (L/min) that will be enough to supply all running fixtures during peak time. Now, for the same example, let’s calculate the litres per minute (L/min) required: So total simultaneous demand becomes 29 L/min.  But just like with a storage system, you should always add around a 2–5 L/min margin to your calculated peak load to cover unexpected usage.  Number of Bathrooms/Showers In Australia, around 80% of people shower daily, so showers are the biggest and most regular use of hot water in most homes. In a storage system, the number of bathrooms affects how quickly the tank will be empty because more bathrooms mean more chances of multiple showers running at the same time (higher simultaneous use), which creates a faster drain on the tank, so you need a bigger tank.  For calculation, you can use this formula:  (Number of Showers) x (9 L/min average shower flow rate) x (average shower time) For example, if you have a 2-bathroom home and two people take a 10-minute shower each, the calculation looks like this: 2 showers × 9 L/min × 10 minutes = 180 litres That means in just 10 minutes, you can use around 180 litres of hot water. If you only have a 160L tank, it will run out before both showers are finished. That’s why you always add a buffer of 50–100 litres, so the system can comfortably handle the showers and any other hot water use happening at the same time without running short.  With continuous flow

When you’re trying to bring down your power bills, heat pump hot water systems easily come up as one of the solutions. And rightly so – they use very little electricity and rely on heat from the surrounding air to warm your water, which works especially well in consistently warm places like Townsville. But whether they’re actually worth it depends on a few things. Performance and cost-efficiency can vary based on the type of system, how it’s installed, and how your household uses hot water. This guide breaks down how heat pump systems work, how different types compare, what they cost to run, and the key pros and cons to consider before making the switch. TL;DR What Is a Heat Pump Hot Water System? It’s an efficient water heater that extracts heat from the air around it and uses it to warm your water. A heat pump almost works like a fridge, but in reverse. Where a fridge removes heat from inside to keep things cold and releases heat into the air, a heat pump takes heat from the air outside and transfers it to the water stored in the tank. So instead of producing heat on its own like a standard electric heater, it simply moves existing heat from outside to inside the water tank, which makes it much more energy- and cost-efficient than other hot water systems.  How a Heat Pump Hot Water System Works A heat pump system works in a simple cycle that happens inside the unit in four steps. Types of Heat Pump Hot Water Systems Based on Configuration  How a system is built and arranged decides where it can be installed, how much space it takes up, and how much the installation costs. 1. Integrated Systems An integrated system is a single unit where the heat pump sits directly on top of the water tank, which is the most common setup you’ll see in Townsville.  Because it’s all in one piece, it doesn’t take up much ground space, as, instead of spreading out, it goes upwards. This makes it easier to fit into outdoor areas like side yards or small utility spaces. Installation is also quicker and cheaper because it’s more of a plug-and-play setup with fewer parts that need connecting. But since these units are quite tall, they might not fit properly if you have a low window, a low roofline, or limited vertical clearance under the eaves. Also, because the fan and motor are fixed on top of the tank, you can’t move the noisy parts away from the installation spot, so placement becomes important. 2. Split Systems A split system, as the name suggests, separates the two main parts. The water tank sits in one spot, while the heat pump unit (the noisy part with the fan and compressor) is placed somewhere else nearby, connected by pipes. This setup gives you more flexibility. If you don’t have enough height for a tall unit, or you want to keep the noise away from a bedroom, window, or outdoor sitting area, you can place the motor further away where it won’t bother you. But it costs more to set up, as installation is complex because your plumber and electrician need to connect two separate units and run extra piping between them.  Types Based on Heat Source All heat pump systems do the same basic job – they take heat and move it into your water. The only difference is where that heat comes from, the air or the ground. 1. Air-Source Heat Pumps An air-source heat pump gets heat from the air around your house. Even when the sun isn’t shining, the air holds ample thermal energy. The system pulls that air in using a fan, captures the heat inside it, and transfers that heat into your water. This is why it works so well in Townsville’s warm, tropical climate, where the air stays warm most of the year. With average temperatures around 28°C in summer and even in the coolest month of July sitting around 20°C, the system always has plenty of heat in the air to draw from, so it doesn’t have to work hard to do its job. You don’t need anything special for installation, either; just install it in a well-ventilated outdoor spot where air can freely move in and out of the unit. 2. Ground-Source (Geothermal) Heat Pumps A ground-source system gets heat from the earth underground. A few metres below the surface, the ground stays at a steady temperature all year round, no matter how hot or cold it is above. These systems use long pipes buried underground to collect that stable heat and transfer it into your water. Although these systems are efficient, they are rarely used in Australian homes because you need major digging work to install the underground pipe system, which makes installation expensive and disruptive. They are only used in large or complex builds, like commercial buildings or high-end properties with plenty of space and budget for underground piping.  Based on Heating Technology This refers to how heat is actually transferred into your water inside the tank. You can’t see it from the outside, but it plays a big role in how long the system lasts, how efficient it is, and how much maintenance it may need over time, so always ask your plumber or supplier about it before you decide on a system. 1. Wrap-Around Coils In this design, the heating coils sit outside the water tank, wrapped around it like a jacket. They don’t touch the water directly and heat it; instead, they heat the tank wall, and that heat then passes through into the water. Because the coils never touch the water, they don’t get coated with minerals found in the hard water in many parts of Australia, which forms buildup and damages components. And since the heating parts stay clean, the system runs efficiently for longer, often 15 years or more. The only disadvantage is that they can

Gas and electric hot water systems differ in how they heat water, how much they cost to run, how quickly they recover, and what space and maintenance they require.  Understanding these differences helps you make the right choice. Because the system you choose directly affects your energy bills, whether you have uninterrupted hot water during peak times, and how well your setup holds up during Townsville’s storms and power outages. In this guide, we’ll break down how each system works and compare them across upfront and running costs, and long-term use, so you can see clearly which option fits your household without second-guessing your decision. TL;DR Gas vs. Electric Hot Water Systems: Quick Overview Before we dive in, a quick note on what we’re comparing here. While both gas and electric systems come in different types, gas systems are typically installed as instantaneous (continuous flow) units, while electric systems are more commonly used as storage tanks. That’s why this guide focuses on comparing gas continuous flow systems with electric storage systems, because this reflects the most common real-world choice for Townsville homeowners. Gas Hot Water System at a Glance A gas hot water system uses a burner powered by natural gas or LPG to heat water.  In a continuous flow gas system, since there is no storage tank, when you turn on a hot tap, a flow sensor detects the moving water and activates the burner. The water passes through a heat exchanger (a series of copper coils) positioned above the flame. The heat is transferred directly to the water as it flows through, so it is heated within seconds before reaching the tap.  These systems use electronic controls to adjust the flame based on demand. If you turn on a second tap, the control panel increases the gas flow to keep the temperature steady. Many units are factory-set to the safe temperature of 50°C, often removing the need for an external tempering valve to mix in cold water. Once the tap is turned off, the sensor detects the flow stop and shuts down the burner immediately, so energy is used only when hot water is actually needed. Electric Hot Water System at a Glance An electric hot water system heats water using immersed heating elements inside a storage tank.  Cold water enters the tank through a dip tube and settles at the bottom, where a heating element is placed. When the thermostat detects that the temperature has dropped below 60°C, which is the minimum storage temperature required under Queensland regulations to prevent bacterial growth, it switches the heating element on to heat the water. The heated water rises to the top of the tank and is drawn out when you open a tap, while fresh cold water flows in, and the cycle continues. Because water is stored at high temperatures, a tempering valve is installed to mix in cold water before it reaches your taps, delivering water at a safe temperature of 50°C to prevent burns. Upfront Investment: What You’ll Pay to Buy and Install Gas Continuous-Flow System Typical installed cost: $1,800 – $3,500 Gas systems are slightly more expensive upfront because they require specialist installation to manage high-intensity burners and exhaust. Costs include: Electric Storage System Typical installed cost: $1,500 – $3,000 Electric systems are cheaper upfront because most Townsville homes already have the wiring and space for a tank. Costs typically include: When Switching Fuel Types Gets Expensive You can see that gas and electric systems both fall into almost the same cost bracket, with a difference of only a few hundred dollars, but this is for a like-for-like replacement. If you change systems and fuel types, the total cost can rise quickly. Running Costs: What You Pay Over Time In Townsville, running costs vary between the two systems depending on your energy rate and daily hot water usage. You can expect to pay:  Gas Continuous-Flow System Annual running cost: $400 – $1,000 Gas costs vary depending on how the gas is supplied. For homes connected to natural gas, you pay a daily supply charge of about $0.80–$1.10. This is a fixed cost just for being connected, which adds $300–$400 per year, even if you use very little gas. On top of that, you also pay for the gas you actually use.  For homes using 45 kg LPG cylinders, a four-person family typically uses 3-5 cylinders annually. Each refill and delivery costs between $120 and $170 per cylinder, and you also pay cylinder rental of about $45–$55 per bottle annually. Altogether, this brings total yearly costs to around $800–$1,000. This makes gas a premium choice for many Townsville households. Electric Storage System Annual running cost: $600 – $900 This estimate covers a typical four-person household using a 250–315 L tank, which uses around 3,300 kWh per year. If your home has solar panels, costs can drop even further. By using a timer or solar diverter, you can heat water during the middle of the day when your system is generating excess power and store it for later use. So, there is no need to purchase electricity from the government grid.  So, gas systems are only cheaper when electric systems use the standard tariff 11. However, when you move to Tariff 33 or use solar, electric storage becomes the more economical choice.  Hot Water Performance & Recovery: How Fast You Can Get Water Performance refers to how quickly a system can deliver hot water and how long that supply lasts during peak use. The recovery rate is how fast the system can heat water again after it has been used. Gas Continuous-Flow System Gas systems are the higher-performance option because a gas burner produces a strong, concentrated flame that transfers heat directly through a heat exchanger, which lets the system heat water very quickly and deliver it within 10 to 15 seconds of turning on the tap. For continuous-flow units, the recovery rate is not really a limitation. Water is heated as it passes through the unit,

Whether you can repair your hot water system’s leak or not comes down to what’s actually causing it. Some issues, like loose pipe connections or a worn valve, are quick and affordable to fix. Others, like a corroded or cracked tank, mean the system itself is failing and needs replacing. In this guide, we’ll walk you through what to do as soon as you notice a leak, how to figure out what’s causing it, and how to decide whether a repair will do the job or if it’s time for a new system. TL;DR What to Do Immediately When You Notice a Leak How Leak Location Helps You Diagnose the Problem Once things are under control, you can take a closer look at where the water is actually coming from. This is important because the location of the leak tells you two key things:  Here’s what each location tells you: Water Pooling at the Top If water is pooling around the top of the tank, it mostly comes from the pipes and fittings attached to the tank’s top. These connections handle the flow of hot and cold water in and out of the unit, and if they become loose or the seals wear out, water can escape. Because these components are external and easy to access, leaks here are generally minor and fixable.  Water Running Down the Side When water runs down the side of the tank, it usually comes from safety valves attached to the side. These valves are designed to release water if the pressure or temperature gets too high.   If the valve starts opening more often or keeps dripping, it can mean the valve is worn out, or the system is under constant stress, like high incoming water pressure or overheating. The plumber will check what’s causing the valve to open and fix it accordingly.  Water Seeping from the Bottom When water pools at the base of the tank, it means the leak is coming from inside the tank itself. Most tanks have a drain point near the bottom, and if water is only leaking from this tap, it’s a replaceable part.  But if water is seeping from behind the metal casing or through the insulation at the bottom, the inner cylinder has likely corroded or cracked, which is not something you can patch up, and the tank itself has failed and needs replacing. Common Causes of a Hot Water System Leaking Now that the leak’s location has given you a clue, it’s time to figure out what’s actually causing it and how to check for sure.  Loose Inlet or Outlet Pipe Connections The pipes going in and out of your tank are one of the most common places for leaks to start. These joints are sealed with threaded fittings and small rubber washers that keep the connection watertight. Over time, the metal fittings made of copper or brass expand and contract as the water heats up and cools down. This repeated movement slowly loosens the connections. The flow of water also causes small vibrations, which weaken the joint even more. On top of that, in North Queensland, constant heat and humidity can dry out and harden the rubber washers, so they don’t seal properly anymore. Once that seal weakens or the fitting loosens, water starts to escape. How to Confirm: Wipe the tank and pipe connections dry with a cloth. Wait 10–15 minutes, then check for fresh droplets at the joint. If the water appears at the pipe but the tank surface stays dry, the leak is likely from the connection. Faulty Temperature and Pressure Relief (TPR) Valve The TPR valve is a safety device located on the side of the tank near the top. Its job is to release a small amount of water if the pressure or temperature inside the tank exceeds the safety limits of around 500 kPa or 99°C, as set by Australian standards. A few drips during the heating cycle are normal. That’s because when water heats up, it expands, which slightly increases pressure inside the tank. The valve releases a bit of water to relieve that extra pressure and keep the system safe. But if you notice a steady drip or a constant stream, something isn’t right. This can happen when: How to Confirm: Take a look at the tundish, the small drain pipe running down from the valve. If water is flowing steadily, gently lift the small lever on the valve for a few seconds to flush out any dirt or mineral bits. Then let the lever close. To check your water pressure, you can attach a simple pressure gauge to an outdoor tap or the cold-water inlet of the tank. Most homes should be around 400–500 kPa.  Leaking Drain Valve The drain valve is the small tap at the bottom of your tank, mainly used for maintenance and flushing. Over time, especially in older tanks, it can start to leak because the valve’s components – plastic or brass – wear out, or sediment and mineral buildup from the local water get stuck inside, stopping them from sealing properly, which eventually causes leaks.  How to Confirm: Take a look at the base of the drain tap. If you see a steady drip or a small puddle or notice white, chalky limescale around the opening, the valve isn’t sealing anymore.  Sediment Buildup and Internal Wear Inside your hot water tank, there’s a sacrificial anode, which is a metal rod that absorbs minerals from local water and slowly corrodes to protect the tank. But if this rod is worn out, minerals in your water (like sand, calcium, and grit) sink to the bottom.  Over time, they form a layer of sediment. The heating element sits just above or embedded in this layer, so the heat it produces doesn’t transfer efficiently into the water. That means the metal directly under the element (the tank base) takes the brunt of the heat because the sediment doesn’t conduct the heat well. Over months and

An instantaneous hot water system, also called a tankless or continuous flow system, heats water on demand instead of storing it in a big tank. That means you don’t have to wait for a big 300-litre tank to refill and reheat; just turn on the tap, and the system starts heating water right away. It’s a space- and energy-saver, and can even save you a bit on your bills. But ‘instant’ can be a little misleading. How fast the hot water actually reaches your tap and whether this type of system is right for your home depends on your house layout, how much water you use, and your plumbing setup. In this guide, we’ll break down how these systems work, how much they cost, their pros and cons, and when they make sense for your home, so you can make an informed decision.  TL;DR How Instantaneous Hot Water Systems Work When you turn on a hot tap, water starts moving through the pipe and into the hot water system. A flow sensor inside the unit detects this movement immediately and sends a signal to the electronic control unit (ECU), which acts as the system’s controller.  The ECU starts the heating process: At the same time, cold water flows into a copper pipe inside the heat exchanger. The burner or elements heat the exchanger, and that heat transfers through the copper pipe into the moving water. Because the water is constantly flowing, it heats up in seconds and continues heating as long as the tap stays on. Before the water leaves the unit, a thermistor (temperature sensor) measures the water temperature as it reaches the outlet of the unit. The system is mostly set to heat water to around 60°C in Queensland homes to prevent bacterial growth and meets Australian safety standards. If the water isn’t at that set temperature, the electronic control unit (ECU) adjusts the heat instantly by:  Once the water reaches that set temperature, it leaves the unit and travels through your pipes. Before it reaches bathroom taps, it passes through a tempering valve, which mixes in cold water to bring it down to a safer 50° to prevent burns.  Finally, when you turn the tap off, the water flow stops. The flow sensor detects this, and the ECU shuts down the burner or heating elements, and the system goes back to standby mode.  Types of Instantaneous Hot Water Systems Based on Energy Source 1. Natural Gas Systems A natural gas instantaneous system is a tankless unit connected directly to your home’s mains gas supply.  These systems can deliver high flow rates because gas burners can produce a large amount of heat very quickly. This high heat output allows the system to heat more water at once, which is why they’re commonly used in family homes with higher hot water demand. In Townsville, homes that already have a gas connection often go with this option because it provides strong, consistent hot water and is typically cheaper to run than electricity. 2. LPG (Liquid Petroleum Gas) Systems An LPG instantaneous system works the same way as a natural gas unit, but instead of being connected to a gas line, it uses gas cylinders stored outside the home. These systems are more expensive to run than natural gas because you not only pay for the gas but also for delivery, bottle refills, and rental of the cylinders. As for performance, there’s no real difference. LPG units still use a gas burner, so they can produce high heat quickly and handle high demand without a noticeable drop in temperature. This makes LPG a practical option for homes that don’t have access to mains gas, which is common in rural or outer parts of North Queensland. 3. Electric Instantaneous Systems Electric instantaneous systems use high-powered heating elements instead of a gas burner to heat water on demand. They’re smaller and more compact because they don’t need parts like a burner, flue, or ventilation, so you can easily have them installed inside cupboards, under sinks, or in tight spaces. But heating water instantly with electricity takes a large amount of energy in a very short time. A standard single-phase power supply can only deliver a limited amount of electricity at once, which is not enough to heat large volumes of water for your entire house while multiple taps are running. To handle higher demand, electric systems require three-phase power. But, most homes don’t have this by default, as single-phase is the standard for residential properties. And if you want to upgrade to three-phase, it often involves changes to the switchboard and supply connection, which is quite expensive. Because of these limits, electric instantaneous systems in Townsville are only used in lower-demand setups, like a single bathroom or a granny flat, where only a small amount of water needs to be heated at a time. Based on Heating Technology 1. Standard (Non-Condensing) Systems A standard instantaneous system is the basic gas model that heats water with a gas burner, and the hot gases created during combustion are vented straight out through a flue. Some of the heat produced in the burner escapes with those exhaust gases, which means not all the energy from the gas goes into heating your water. Because of this, these units are less energy-efficient than newer designs. These systems are popular in many older homes in Australia because they are simple and cheaper to buy upfront. 2. Condensing Systems A condensing instantaneous system is a high-efficiency version of a gas unit. It works like a standard system but with one key improvement: it reuses heat from the exhaust gases. The hot gases from the burner normally leave through the flue. In a condensing system, these gases pass through a second heat exchanger, which transfers much of that leftover heat into the incoming cold water. This means more of the gas energy actually heats your water instead of being wasted. However, these systems cost more upfront, but in Townsville homes