What is a Spa Heat Pump? (and how to choose the right one)


Choosing the right heating and cooling solution is an important decision that can significantly affect the running costs of your spa.

Whether you are installing a new spa pool or swim spa or upgrading the heating system on your existing spa, this article will explain everything you need to know about spa heat pumps and how to choose the right one for your spa.

Most spas and swim spas come with a built-in electric spa heating element that will heat your spa, however, a heat pump can use 75% less energy than these electric elements - resulting in significant savings on power over time.

If you plan on using your spa regularly, a heat pump is an investment that will save you significantly on your spa running costs.


What is a Spa Heat Pump?



A heat pump is a stand-alone unit that sits outside near your spa pool and uses a compressor and a fan to extract heat from the air and transfer it to your spa water. 

A heat pump operates much more efficiently than a heater element - meaning you will use a lot less electricity to heat your water. You could use up to 75% less energy than an electric heater element and 55% less energy than a gas heater. By drawing in heat energy from the ambient air, they only use a fraction of the power to generate the same amount of heat.


Heating cost savings with a heat pump

Source: www.spanet.com.au


Depending on the outside air temperature, your heat pump will adjust it’s fan speed to allow it to heat the most efficiently.

A heat pump (like an air conditioner in your home) can also operate on a reverse cycle mode and cool the water in your spa - ideal for getting the temperature just right in the warmer months of the year!



What is the best spa heat pump in Australia? (Reviews, Pricing, Pros & Cons)

We review 3 of the best spa heat pumps available to the Australian market. This section provides a review of the heat pump outlining the benefits, an approximate price range and some of the pros and cons of each model.


SpaNet® SV series heat pump review

SpaNet® SV Series Heat Pump

The SpaNet® SV series heat pump is designed to interface with the SpaNet® SV series spa controller. This means you can take full advantage of the dynamic thermal tuning technology within the SV controller - which optimises your power usage to get you the most efficient heating. Installation is also very easy - it just plugs straight into your SV controller.

Because the SV series heat pumps interface with your spa controller, you can carry on controlling your temperature direct from your spa touchpad. This also means you can heat your spa up more quickly by utilising both the heating from the internal heater element and the heat pump working together.

The SpaNet® SV series heat pump is very efficient at heating your water and cooling it down in the warmer months of the year. This means you can enjoy your spa all year round and only pay a fraction of the amount towards electricity compared with a standard heater element.


SpaNet® SV series heat pump Pricing

The SpaNet® SV series heat pumps come in three sizes. The prices for each are listed below (accurate at the time of writing).

5.5kW Heat Pump $2,658.95 incl GST
8.8kW Heat Pump $3,092.30 incl GST
12kW Heat Pump $4,162.30 incl GST

*Prices do not include delivery or installation.


SpaNet® SV series heat pump Pros

  • Connects directly with SpaNet® SV Spa Controllers for easy install and easy control direct from your spa touchpad.
  • Integrates fully and uses all of the energy saving functions in your controller to make it even more efficient!
  • Save up to 75% on your spa heating bill - thousands of $$$ over the life of your spa!
  • Remote control your temperature using the SpaNet® mobile app (or Vortex® app in a modern Vortex® Spa.)
  • Low carbon technology and safe refrigerant technology means SV heat pumps are safe for the environment.


SpaNet® SV series heat pump Cons

  • Will only work if you have a SpaNet® SV series controller in your spa.


SpaNet® SV series heat pump Technical Specifications (8kW version)

Heating Capacity 8.6kW       
Current Draw 7.8A
Cooling Capacity 6.0kW
Refrigerant R410A
Compressor Toshiba
Heat Exchanger Titanium / PVC
Noise dB(A) 49
Water Flow (Litres / min) 50





SpaNet® PowerSmart universal heat pump review

If you don't have a SpaNet® controller, but still want to enjoy the benefits and cost savings of the SpaNet® heat pump range, a PowerSmart universal heat pump is a perfect choice.

The PowerSmart range of heat pumps can be connected to most spa pools and swim spas, even if you don't have a SpaNet® SV controller. You can still enjoy massive savings (up to 75%) on heating costs for your spa and enjoy the benefits of efficiently cooling your spa water in the warmer months of the year too.

The SpaNet® PowerSmart heat pumps use an eco friendly refrigerant which is more energy efficient and doesn't deplete the ozone.


SpaNet® Power Smart Series Universal Heat Pump


SpaNet® PowerSmart series Heat pump Pricing

PowerSmart 6.0kW Heat Pump $2,835.50
PowerSmart 8.3kW Heat Pump $3,274.20
PowerSmart 14.0kW Heat Pump $4,483.30
PowerSmart 17.0kW Heat Pump $5,617.50
PowerSmart 19.0kW Heat Pump $6,088.30


SpaNet® PowerSmart series Heat pump Pros

  • Suitable for most brands of spas and controllers (Doesn't require a SpaNet® controller)
  • Save up to 75% on your spa heating bill.*
  • Heating AND cooling operation. From 10 to 40 degrees
  • Eco-Friendly Refrigerant R410A does not cause ozone depletion and achieves higher performance with reduced power usage


SpaNet® PowerSmart series Heat pump Cons

  • Does not interface with your spa controller


SpaNet® PowerSmart series heat pump Technical Specifications (8kW version)

Heating Capacity 8.6kW       
Power Inpuit 1.5kW
Max Current Draw 7.2A
Cooling Capacity 5.8kW
Refrigerant R410A
Compressor Panasonic
Heat Exchanger Titanium / PVC
Noise dB(A) 49
Water Flow (Litres / min) 83





SENSA-HEAT PI Series heat pump review

Utilizing the latest inverter technology, SENSA-HEAT PI Series heat pumps offer world-class efficiency, meaning massive cost savings for you whilst running quieter than other units!

Plus they look pretty classy and sleek in a class dark grey. Their innovative design means the fan is not visible from the front face, so they blend nicely into your outdoor space.

The SENSA-HEAT PI Series heat pumps come Wifi enabled, so you can control your spa temperature remotely using the mobile app.

They come in a range of sizes from 9kW up to 28kW to suit spas, swim spas and even pools.

The invertor technology enables you to heat your spa water efficiently and it can work in reverse to cool your water in summer!


Sensa-Heat PI Series Invertor Heat Pump


SENSA-HEAT PI Heat Pump Pricing

Sensa-Heat PI Series 9.0kw Heat Pump $3,565.67
Sensa-Heat PI Series 13.0kw Heat Pump $5,075.75
Sensa-Heat PI Series 17.0kw Heat Pump $6,499.01
Sensa-Heat PI Series 21.0kw Heat Pump $8,016.64
Sensa-Heat PI Series 28.0kw Heat Pump $9,188.84


SENSA-HEAT PI Heat Pump Pros

  • Save on power with the Inverter Technology for a soft start
  • Get your spa temperature just right with reverse cycle, heating & cooling
  • Quiet operation with patented back discharge
  • Control remotely with your mobile phone!
  • Long lasting reliability with the Mitsubishi DC twin-rotary invertor compressor


SENSA-HEAT PI Heat Pump Cons

  • Does not interface directly with your spa controller
  • Lower cooling capacity


SENSA-HEAT PI Heat Pump Technical Specifications (9kW version)

Heating Capacity 9.0kW       
Current Draw 10A
Cooling Capacity 4.4kW
Refrigerant R32
Compressor Mitsubishi
Heat Exchanger Titanium
Noise dB(A) (at 1m) 36.8-46.2
Water Flow (Litres / min) 50-70





How a Spa Heat pump works

Without getting too technical, here’s a quick overview of the process a heat pump uses to transfer heat energy from the ambient air to your spa water!

  1. The liquid refrigerant inside the heat pump passes through an evaporator where it absorbs heat from the air and transforms into a gas
  2. An electric compressor then compresses the gaseous refrigerant
  3. As the gas is compressed, its temperature increases
  4. The warmed up gas moves into a condenser, where the heat is transferred to the water
  5. The refrigerant gas returns to a liquid state as it passes heat energy to the water
  6. The liquid flows through an expansion valve to release pressure and cool down
  7. The cycle repeats

Top 5 things to look for in a spa heat pump

1. Interfaces with your spa controller 

If you’re using a SpaNet® SV series controller in your spa or swim spa, you can interface a SpaNet® heat pump directly to your controller, meaning that it can be controlled directly from your spa’s control panel or even via the SpaNet® mobile App. This means you can get the full energy -saving benefits from your SV controller. Plus it is much easier to install!


2. Heating Capacity 

Check the heating capacity level of the heat pump to ensure it’s sufficient for your spa or swim spa. Refer to the table below for our recommended sizes. Heating output is measured in kilowatts (kW).


3. Certified for use in Australia (AS/NZS 60335) 

Not all heat pumps have the correct electrical certification for use in Australia. Make sure you select one that has been certified to the correct standard to ensure you and your guests are kept safe.


4. Noise of operation

Check the sound level rating to ensure it’s not going to be too loud. (You may need to check with your local council regarding noise levels that are allowed in your neighbourhood). Sound levels are measured in decibels (dB /dB(A)). Anything with an ambient noise level under 55dB (A) is considered very quiet.


5. Eco-Friendly Refrigerant

Make sure the heat pump uses am eco-friendly refrigerant. Look for either R32 or R410A rated refrigerant which is safe for you and for the environment.


What size heat pump do I need for my spa? 

As a general rule, spas up to 2,500L in volume will need a heat pump of around 5.5kW to 6kW. 

A bigger spa or swim spa with a volume of up to 5,000L will need a heat pump with power output of 9kW.

The bigger the heating unit, the faster it will heat up. (But bigger heat pumps will use more power too!)

Heat pump size guide

Spas up to 2,500L 5.5kW - 6kW
Spas and Swim Spas larger than 2,500L 8kW - 9kW
Swim Spas larger than 7,000L 12kW+



How much does it cost to replace a spa heat pump?

Heat pumps start at around $2,600 for a 5.5-6kW heat pump. Or around $3,100 for an 8kW heat pump. Although there is an investment up front for a new spa heat pump, you'll find you're using a lot less electricity going forward, saving you money on your spa running costs.



How do you heat up a spa quickly with a heat pump? 

The only time you’ll need to heat your spa is when you are starting with cold water from empty.  Then after that, the set temperature will keep your spa consistent. (Remember, it is more efficient to maintain a water temperature rather than re-heat from cold each time).

Here are a few things to check to help your spa heat up quickly and efficiently.


1. Keep your cover on while heating to avoid heat loss.

Your spa can lose a lot of heat if it is not covered, so keep your spa covered as much as possible while it's heating up and when not in use.


2. Check the quality of your cover

A waterlogged cover, won’t insulate. Warm air can also escape around the hinge block or from the rim of your cover if it is not sealing in these areas. If your cover is absorbing water or worn, it’s time to consider replacing your spa cover.


3. Make sure your insulation is up to date 

Check if the insulation around your spa cabinet is present and in good condition. If you don’t have insulation, consider adding it.

Can I run a heat pump in cold weather? 

Yes, you can as long as the ambient temperature does not drop below 10 degrees. If your temperature drops below this, the heat pump will switch off. In modern spas, when this happens, your controller automatically switches back to the electric heater to maintain the temperature in your spa.


How long does it take to heat a spa from cold? 

As a general rule, a spa pool will heat  0.5-1 degree per hour. Portable spas (up to 1,500L) will take from 18-24 hours to heat.


How long does it take to heat a swim spa?

A swim spa will take up to 72 hours to heat.

How do I keep my spa warm?

Some of the ways you can improve the efficiency of your spa heating include;

  • Making sure your spa cover is in good condition and sealing tightly
  • Checking the condition of your insulation in your spa cabinet (Or adding insulation if you don’t have any).
  • Setting a lower water temperature. Dialling down your set temperature by just 1 degree may not even be noticeable, but could make a big difference to your heating costs.


Should I leave my spa heater or heat pump on?

Yes. Modern spas are designed to be left on to maintain the temperature. It uses less power to leave it on and maintain the temperature, rather than reheating from cold.

If you go away for an extended period of time, turn your spa down to 10 degrees and put it on away mode and it will only circulate water daily without using any energy for heating.

If your spa is connected the mobile app, you can login to the app the day before you come back and reset your desired temperature. (It will generally take 12-18hrs to heat up)


What is the ideal spa temperature for Australia? 

Keep your spa temperature between 32 - 34 degrees (Celcius) if you have children.
if you like hot water - you can set it up to 38 degrees for adult use (Celcius).

If you want to save money, setting your temperature lower will reduce your energy costs.


What temperature should I keep my spa when not in use?

If you’re going away for a week or more, you can set your spa temperature to 10 degrees and set your filtration system to just circulate once per day. 

If you only use the spa at the weekend, you can set your spa to ‘week mode’ which disables heating and filtration just runs for 1 hour per day, then from Friday to Sunday, it runs normally.


Can I run my spa on a solar heating system? 

Yes, all Spa World spas can be run off solar power, however solar only works when the sun is out. What we find is that the spa ends up getting really hot in summer and not hot enough in winter, which is opposite to the way you probably want to use it!


Can a spa heater or heat pump heat a pool?

No. Because the chlorine requirements and heating requirements are different in a pool, they are not designed to be interchangeable. We recommend a specific pool heater.


What is the most energy-efficient spa heater? 

Inverter heat pumps are up to 6 times more efficient than an electric heater element. In this article we have explained how a spa heat pump works, to read in detail how a spa heater works.

Got more questions about spa heaters and heat pumps? 

Talk to us on live chat, or email us and we'll be happy to help!


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