Heat Pumps: Your 2024 guide to all things heat pumps.

What Is A Hot Water Heat-Pump?

The word Heat-pump gets thrown around a little bit but what actually is it and how can it save you energy and in turn, cash money? In this article we are going to explain everything you need to know about hot water heat pumps.

When people say ‘heat-pump’ it can mean many different things. This is because a heat-pump is the type of technology that is being used. Some of the heart-pumps that are used in our day to day lives are things like, a traditional air conditioner, pool heat-pumps and most importantly, hot water heat-pumps.

In the example of a hot water heat-pump, it works by using a refrigerant to extract heat from the air outside of your home and turns it into energy to heat the water in your hot water tank. They work in a very similar way to reverse-cycle air conditioners when they are running on a heating setting, but instead of warming air, they heat the water inside your tank. 

The coolest part (pardon the pun) is that hot water heat-pumps use a whopping 60-75% less energy than traditional hot water systems because they use the electricity to run the heat pump and not directly try to heat the water with an element. The net result, you get hot water when you need it and it’s cheaper. 

Plus, if you have solar or solar and a battery, you can run it on your own cheap, clean, green energy so it is a double win.

Types of Hot Water Heat-Pumps

There are two main types of hot water heat pumps. Split and integrated. 

In split systems, the storage cylinder is separate from the evaporator, fan and compressor. The two units are then connected by refrigerant piping. The heated gas is pushed through a “heat exchanger” in the main cylinder which in turns, heats up your water! These look very much like your traditional split system aircon if it was connected to your hot water system. 

There is a bit of a hint in the name with an integrated system. It’s all integrated into one system! Often the storage cylinder sits at the bottom with working bits and pieces (including evaporator, fan, compressor, and condenser) all sitting on top. 

Both are perfectly good options however at Green we typically sell integrated systems more than split.

Where are they made?

This really depends on what one you buy but the reality is like a lot of things, most heat pumps are made in China. In our opinion, there isn’t a meaningful relationship with where they are made and quality. Some of the heat pumps coming out of China are absolutely world class. 

If you really want something from somewhere, make sure you ask before you sign on the dotted line for your next hot water solution.

What is the reheat rate?

The reheat rate or often called the recovery rate is litres per hour the system can get water back up to a hot temperature for your home to use. This can be important if you are a high usage hot water home. If you use it sparingly, probably nothing to worry about but if you do love a long hot shower, make sure you get a system with a good reheat rate so you can always have hot water when you need it. 

Some heat pumps will have backup boosters which will cover you if the outside ambient temperature is a bit lower and needs some help. 

Other factors that will impact how fast your system heats your water up are: 

• The actual system itself and product design
• The temperature of the watering coming into the system. Obviously in winter, it is colder and summer warm etc. 
• The temperature and humidity of the ambient air around the system

Does it matter where I live? 

This is a common question when people are looking at installing a heat pump hot water system. The reality is no. It always makes sense to install a heat-pump. Even in cold climates there is still “heat” in the air that can be used to heat your hot water. The incredible efficiency of these systems means that even in the southern parts of Australia, heat pumps can still work well and produce good savings when compared to traditional electrical and gas systems. 

They do work more efficiently with higher external air temperatures but, like we mentioned, they still work well when it is cold so fear not! Just to be clear on this, when we say “heat” we mean heat as energy. Hence, even when it is pretty dang cold to us, there is still “heat” that can be useful to a heat-pump. 

Heat-Pumps and Electricity 

Heat-pumps still use electricity. Just much, much less than a traditional hot water system. The cool thing is, they have lots of functionally that means on top of their inherent energy savings, if you are a smart cookie, you can save even more!

Firstly, it is just an appliance deep down so if you have solar, or solar and a battery your heat pump can use your clean green renewable energy to run. That is the holy grail for a low cost electrified household. 

Some other things that you can do to keep costs down. Many will have a holiday mode. This will reduce it to a bare minimum while your away so it isn’t keep water hot for no reason. Plus, if you don’t have solar or a battery you can set them up on a timer or in their app (depending what system you get) to run with electricity is cheap. Think of your shoulder or off-peak times. This means while it does use way less energy, when it does need to take some power from the grid it will take it when it is as cheap as possible. 

What warranty comes on a heat-pump?

The warranty you will get on your heat-pump can vary significantly and are generally broken into two key categories. The tank or cylinder will generally have its own warranty, as will the actual workings of the heat pump itself. 

At the time of writing this, heat pump warranties in Australia varied from 2 - 8 years for the heat pump/compressor and 5 - 15 years for the tank. 

Like anything, a warranty is only as good as the company behind it. It is always important to consider the warranty when purchasing any product but also make sure you are comfortable with who you are buying it from. A super long warranty is very useful when the company providing it doesn’t exist anymore.

What size heat-pump should I get?

Working out what size hot water heat pump to get is vital to ensure you get hot water when you need to while producing the best value for many.

A few things to consider at the start, Bigger isn’t always better when it comes to hot water heat pumps. For example, if you use a lot of hot water but you use it consistently through-out the day, a huge tank might not actually be very useful. What you might be more suited to is a smaller tank with a good recovery rate(we talk about this above). However, if you use lots of water at night time, if the whole family comes home and wants a hot shower for example, a big tank might be the best option to ensure there is lots of hot water available in a short period of time.

Tanks generally range from 150 litres to 400 litres with a rule of thumb that the smaller end will service 1 - 3 people and the top end covering 6+.

If you are unsure, it is always best to ask so have a conversation with the team at Green today and save the headache of trying to work it out for yourself.

Are there any Government Incentives or Rebates available? 

There are a few different incentives that are available, some nationwide, some are state by state. 

Heat pumps are eligible just like solar is for STC’s (Small-scale technology certificates). The bigger the pump, the bigger the incentive. We trade those on your behalf and give them to you as a point of sale discount. 

When it comes to the state by state incentives, it is best to speak to a Green consultant to see what you are eligible for. They are a bit more fluid (great pun), are different from state to state and they do change a little more frequently. 

Conclusion

Look, some may say we are biased but we think hot water heat-pumps are great. They are super efficient, have great warranties, are a tried and tested technology and save you a bunch of money along the way. If you need a new hot water system, building a new home or just want to go for a cheaper greener option, we would highly recommend a heat pump to keep your water roasty toasty, clean, green and cheap just for good measure.