What size heat pump hot water system do I need? It’s a common question—and an important one. The wrong size can leave you with cold showers or higher energy bills.
If your system is too small, you’ll run out of hot water when you need it most. Too big, and you’ll waste energy heating water you don’t use, costing you extra money. So, this guide will help you pick the right hot water system size to keep your showers warm, lower your energy bills, and ensure your home runs efficiently.
Key Takeaways
- Heat pump hot water systems use less power than regular water heaters, helping you cut down on your electricity bill.
- Choosing a system that matches your household’s hot water use means you won’t run out or waste energy on extra heating.
- A professional can help you pick the best system and install it properly so it runs efficiently and lasts longer.
Table of Contents
Understanding Heat Pump Hot Water Systems
Heat pump water heaters are changing the way we heat water at home. They use much less energy than traditional electric water heaters or gas systems, helping you save money on energy bills while reducing your environmental impact. If you choose the right hot water system size and use an off-peak tariff, you can cut costs even more—and you might even get away with a smaller system that still meets your household’s hot water requirements.
To get the most out of your heat pump hot water system, it helps to understand how they work and the different hot water systems available.
If you’ve noticed weak water pressure when using hot water, it could be due to various factors like plumbing issues or system limitations. Our article on Why Is My Hot Water Pressure Low? can help you troubleshoot common causes and solutions.
How Heat Pump Hot Water Systems Work
Instead of using natural gas or electricity to directly heat water, heat pump systems pull warmth from the surrounding air and use it to supply hot water efficiently. Here’s how it works:
- An evaporator fan pulls in ambient air, even in warmer climates or during off-peak times.
- The system absorbs heat from the air and passes it through a special process that boosts the temperature.
- The heated energy is transferred to the storage tank, keeping your hot water outlets supplied.
Some heat pump water heaters come as an integrated system with the storage system and heating unit combined. Others have a separate unit, with the evaporator and tank installed apart. The best location for your system is somewhere with plenty of ambient air temperature to help with energy efficiency, especially if you live in a cold climate where performance can drop.
Types of Heat Pump Systems
There are different types of heat pump hot water systems, and the best one for you depends on your space and needs.
- Integrated Systems – These have the heat pump and storage tank built into one unit. They’re simple to install but can be a bit bulky. Most people put them outside on the ground.
- Split Systems – These work like an air conditioner, with a separate heat pump unit and a storage tank. They’re great if you don’t have much outdoor space since they give you more flexibility in how you set them up.
If you’re also thinking about solar hot water systems, some heat pump units can be paired with solar systems to make them even more energy-efficient. Choosing the right system depends on your household size, available space, and how much hot water you use each day.
Calculating Your Household's Hot Water Consumption
Before choosing a heat pump hot water system, it’s important to know how much hot water your home actually needs. If you get a system that’s too small, you might run out of hot water when you need it most. If it’s too big, you’ll waste energy and spend more than necessary.
By understanding your family’s hot water usage, you can find a system that’s just the right size—giving you reliable hot water without wasting energy or money.
Factors Influencing Hot Water Usage
Your household size and daily habits play a big role in how much hot water you need. Think about:
- How many people live in your home? More people means more hot water consumption—especially during peak demand times like mornings and evenings when everyone’s showering or using the kitchen.
- How many bathrooms do you have? More bathrooms often mean a larger system is needed to keep up with demand.
- What appliances use hot water? Washing machines, dishwashers, and multiple showers running at the same time can quickly add up.
- When do you use the most hot water? Evenings tend to be the busiest, with dishes, showers, and laundry all happening at once.
Knowing when and how you use hot water helps you pick a hot water system size that keeps up with demand while staying energy efficient.
Average Daily Water Use Per Person
On average, each person in a home uses 75 to 100 litres of hot water per day for things like:
- Showering
- Washing dishes
- Doing laundry
So, if four people live in your home, you’ll likely need 300 to 400 litres of hot water each day. This is a good starting point when choosing the right heat pump hot water system—making sure it’s big enough for your needs but not so large that it wastes energy.
By understanding your water usage, you can find the perfect system that keeps your home running smoothly while helping you save energy and reduce your energy bills.
Choosing the Right Size Heat Pump Hot Water System
Picking the right heat pump hot water system is important—it keeps your hot water running without wasting energy or money. If your system is too small, you’ll run out of hot water when you need it most. If it’s too big, you’ll waste energy heating water you don’t use.
The key is to match your system to your household size and hot water usage. Getting professional advice specific to your needs can also help you choose the best option for your home. Here’s a simple guide to help you decide:
Small Households (1-2 People)
For a small apartment or a home with one or two people, a heat pump hot water system with less than 200 litres is usually enough. So, why choose a smaller system?
- Saves energy and lowers energy bills
- Takes up less available space
- Perfect for homes with low hot water consumption
Some models, like the EVO150-1 Heat Pump, can reduce hot water costs by up to 75%, making them an energy-efficient choice.
Medium-Sized Families (3-4 People)
If you have three to four people in your home, you’ll need a system with a 200 to 300-litre capacity. Medium-sized system:
- Provides enough hot water for everyday use
- Keeps up with peak demand in the morning and evening
- Balances energy efficiency with household needs
A properly sized system means you won’t run out of hot water while still keeping energy consumption low.
Large Households (4 or More People)
For larger families or homes with multiple bathrooms, go for a 300-litre or larger heat pump hot water system. A larger system:
- Meets high hot water requirements
- Ensures enough supply during busy times
- Works well for homes with varying household sizes and high water usage
On average, each person uses 50 to 70 litres of hot water per day, so multiply this by the number of people in your home to estimate your needs.
Choosing the right size hot water system is key to making sure your household has enough hot water without wasting energy. If you’re unsure what size is best for your home, check out our guide on What Size Hot Water System Do I Need? for a guide.
Other Considerations When Sizing Your Heat Pump System
Picking the right size hot water system isn’t just about household size and hot water usage. Other factors, like insulation, climate, energy source, and available space, also affect how well your system works.
Did you know that good insulation can make a huge difference in how much energy your heat pump hot water system uses? Homes with better insulation need less energy to heat water, which means lower energy bills.
Also, where you place your hot water heater matters. If you put it in a central location, it can reduce energy consumption by up to 35%. Plus, larger storage tanks lose more heat over time, which can be a problem in small households that don’t use as much hot water.
Climate and Ambient Air Temperature
Heat pumps work best in warmer climates because they pull heat from the surrounding air. The warmer the air, the less energy the system needs to heat water. But if you live in a cold climate, your system might need to work harder—especially when temperatures drop below –5°C.
If you’re in a colder area, you may need a larger system to keep up with your hot water needs. So, before choosing a heat pump hot water system, think about your local climate and how it might affect energy efficiency.
Available Space for Installation
Before installing a heat pump hot water system, check if you have enough available space. The compressor unit needs good airflow to work properly, so it shouldn’t be squeezed into a tight spot or blocked by walls.
You’ll also need space around the storage tank for maintenance and air circulation. Making sure you have the right setup will help your system run efficiently and last longer.
Optimising Energy Efficiency and Cost Savings
Getting the most out of your heat pump hot water system isn’t just about picking the right size hot water system. There are a few simple ways to boost energy efficiency and save money on your energy bills.
Did you know that heat pump water heaters are 2 to 3 times more efficient than standard electric water heaters? That’s because they don’t generate heat directly—they pull warmth from the surrounding air instead. This means they use 60–75% less electricity, which can lead to big savings over time.
If you’re not sure which hot water system is best for your home, talking to a professional can help. They can recommend energy-efficient options and make sure you’re getting the most out of your new system.
Using Timers and Off-Peak Tariffs
Want to cut down your energy bills even more? Try heating your hot water during off-peak times when electricity is cheaper. Many power companies offer off-peak tariffs, which means you’ll pay less if you heat your storage tank at night when demand is low.
You can set a timer on your heat pump hot water system so it heats up at the best time. But to make this work, your tank size needs to be big enough to store enough hot water for the whole day. Using off-peak power not only helps you save money but also reduces strain on the power grid!
Regular Maintenance for Optimal Performance
Like any hot water heater, your heat pump system needs regular maintenance to stay energy-efficient and last longer. Heat pumps are highly efficient, but they need to be in top shape to keep outperforming standard electric water heaters and lower energy consumption.
Simple maintenance tasks can make a big difference, including:
- Cleaning the evaporator fan to keep airflow clear.
- Checking for dust and debris that could reduce efficiency.
- Ensuring the refrigerant level is correct for optimal performance.
Investing in a heat pump hot water system can save you money in the long run, but upfront costs vary depending on size, efficiency, and installation needs. If you’re wondering how much you should budget for a new system, our guide on How Much Does a Hot Water System Cost? can help.
Professional Advice and Installation
Getting a heat pump hot water system (or even a solar hot water system) is a big decision, and making sure it’s installed properly is just as important. That’s where the pros come in!
A professional can help you pick the most energy-efficient system for your home and avoid costly mistakes during installation. They also stay up to date with the latest tech, so you get the best energy-saving options, whether it’s a solar heater, an electric system, or one with a booster function for those colder days.
- Avoid costly mistakes – A pro will make sure your system is the right size, matches your flow rate needs, and is installed correctly, so you don’t waste energy or money.
- Better performance & efficiency – When installed properly, your hot water system will work better, last longer, and stay cost-effective.
- Save money in the long run – A well-installed system runs more efficiently, cutting down your energy bills over time. The Australian government also offers rebates for certain energy-efficient systems, so a pro can help you see if you’re eligible.
Installing a heat pump hot water system isn’t a DIY job—it requires a licensed professional. At MGR Plumbing, we have experienced hot water plumbers in Melbourne who can install, repair, and maintain your system.
Choosing a Qualified Installer
A skilled installer makes all the difference, helping you get the most out of your heat pump or solar hot water system while keeping your home’s hot water running smoothly!
- Look for licensed professionals – Make sure your installer has the right qualifications and meets local standards. If you have a gas supply, they should also be certified for working with gas systems if needed.
- Check reviews & reputation – Look for a trusted expert with positive customer feedback.
- Compare quotes – Get a few estimates to compare pricing and services, so you get the best deal without compromising on quality.
Summary
Picking the right heat pump hot water system isn’t just about getting hot water—it’s about saving energy, cutting costs, and keeping your home comfortable. By figuring out how much hot water your household needs and thinking about things like climate and available space, you can find the perfect system to suit your lifestyle.
Getting expert advice and keeping up with regular maintenance will help your system last longer and run more efficiently. With the right setup, you’ll enjoy steady hot water, lower energy bills, and a more eco-friendly home. Make the smart choice today!
If you’re looking for a plumber in Melbourne, MGR Plumbing offers expert plumbing services across Melbourne, ensuring your system is installed correctly and efficiently.
Frequently Asked Questions
How do heat pump hot water systems work?
Think of it like a reverse fridge! Instead of cooling things down, a heat pump pulls warmth from the air and uses it to heat your water. Unlike traditional electric or gas systems, heat pumps use less energy, making them a cost-effective and eco-friendly choice.
What factors should I consider when choosing the size of my heat pump hot water system?
The right heat pump hot water system size depends on a few key things. First, think about how many people live in your home. More people means more hot water consumption, so you’ll need a bigger system.
Your daily routine also plays a role—if everyone showers at the same time, your system will need to handle that peak demand. Climate matters, too, as heat pumps work best in warmer climates, but some models are designed for cold climates. Lastly, make sure you have enough available space for the system to be installed properly.
How much hot water does an average person use daily?
On average, a person uses between 75 and 100 litres of hot water per day. This includes showers, washing dishes, doing laundry, and other daily activities. Understanding your household size and usage patterns can help you pick the right system and avoid running out of hot water or overspending on a system that’s too big.
What are the benefits of professional consultation for heat pump hot water systems?
A qualified installer can help you choose the right system for your home, ensuring it meets your hot water requirements without wasting energy. They can also make sure your system is installed correctly so it runs efficiently and lasts longer. Getting professional advice helps you avoid costly mistakes, keeps your energy bills in check, and ensures your system performs at its best for years to come.
How can I make my heat pump water heater more energy efficient?
There are a few simple ways to save energy and lower costs. Using off-peak tariffs allows you to heat water when electricity is cheaper, which can make a big difference in your energy bills. Keeping up with regular maintenance—like cleaning the evaporator fan and checking the system for dust—helps it run smoothly and efficiently. If you’re unsure how to get the most out of your system, seeking professional advice specific to your setup can ensure you’re maximising your savings and efficiency.
