Thermotec Inverter Pro Horizontal Heat Pumps with Wi-Fi for Swimming Pools or Koi Ponds 9kw to 24kw


GTIN: 0796562385395


Thermotec Inverter Pro Horizontal Models with Wi-Fi Heat Pumps –  Sizes 9kw to 24kw

Update Sept 2023: The new Thermotec Inverter Pro Horizontal models with wifi are all in stock. Order now while stocks last. Includes FREE wifi module !

1. Description

HeatPumps4Pools are the leading specialist supplier of swimming pool heat pumps. We have many years of experience in the market and have used our expertise to research and design our own range of swimming pool heat pumps.

The New Thermotec Inverter Pro Horizontal range of pool heat pumps really do offer the best in terms of efficiency, performance, reliability and low noise operation.

The New Thermotec Inverter Horizontal range are fully inverter driven. This means that they automatically adjust the speed of the fan and compressor to precisely match the heat demand from the pool.

The ability to adjust the output of the heat pump allows the New Thermotec Inverter Pro Horizontal to deliver greatly reduced running costs with COPs of up to 13. This means that for every 1kw of electricity used by the heat pump, 13kw of heat is delivered to the pool. This delivers reduced running costs compared with other heat pumps on the market

In addition the inverter technology has a reduced electrical startup requirement, making them ideal for properties with a sensitive or limited electrical supply.

They have larger evaporators (fins) which gives more surface area to extract heat at low air temperatures. This allows the Thermotec Inverter to produce more heat than competitor heat pumps at low air temperatures, making them the best choice for koi ponds and indoor pools which are used all year round. The larger surface area also gives higher efficiency and reduced running costs all year round.

Thermotec Inverter with WifiThermotec-inverter-Pro-pic7 24kw
Thermotec Inverter Pro 9kW, 12kw, 17kw, 20kw – Single Fan, HorizontalThermotec Inverter Pro 24kW – Twin Fan, Horizontal

We also have the New Thermotec Inverter Pro Vertical fan 29kw single phase and 34kw single and 3 phase models. Please Click Here to see details and pricing

2. Features

  • Fully inverter driven with variable speed fan and compressor to deliver the lowest running costs with maximum heat output
  • High efficiency with COPs of up to 13. This means that for every 1kw of electricity used by the heat pump, 13kw of heat is returned to the pool.
  • The desired water temperature can be adjusted in steps of 0.1 °C.
  • Equipped with an easy to use 5-inch colour touch screen display / control panel.
  • Remote control and monitor your heat pump via an app on your smartphone
  • Remote support from HeatPumps4Pools via the wifi module – supplied free of charge with each heat pump
  • Top quality Mitsubishi variable speed inverter compressor
  • Brushless variable speed DC fan motor – very efficient with extremely quiet operation
  • Control panel is lockable to prevent tampering with the pool set temperature (useful for rented properties)
  • Display shows temperature & power consumption curves to monitor the performance of the heat pump
  • Six different models:9kw, 12kw, 17kw, 19.5kw, 24.2kw, 28 kw and 34kw
  • All models single phase power (ie 220v to 240v)
  • Suitable for pools, swim spas, hot tubs and koi ponds etc
  • Desired water temperature can be set from +10c to +40c
  • Soft start with reduced electrical startup requirements for properties with sensitive or limited power supplies
  • Low noise, variable speed fan.
  • Corrosion resistant case
  • Microprocessor controlled
  • Fully programmable via the colour touch screen control panel
  • Automatic hot gas defrosting.
  • Ideal for use on koi ponds – fully programmable temperature accuracy (swing) – down to 0.5c above and below desired water temperature. No external thermostat required.
  • No need to purchase a separate external thermostat for accurate temperature control
  • Titanium heat exchanger – resistant to corrosion from chlorine or salt pools.
  • Operates in air temperatures as low as -15 °C.
  • Capable of heating and cooling, all year round.
  • Wifi module – control the heat pump from your smartphone or any web browser
  • Built in timer function
  • Built in water flow switch
  • Includes condensate drain hoses and drain spouts to allow condensation water to be diverted to a flower bed etc.
  • Refrigerant gas type – R32 for all models except 34kw single phase model which uses R410a refrigerant
  • 3-Year Parts & Labour Warranty on all parts

Themotec Inverter Heat Pumps Specifications

3. Key Benefits of the New Thermotec Inverter Pro Horizontal Range

  • The Thermotec Inverter heat pumps have larger size evaporators (fins). This gives them more surface area and allows more heat to be captured from the air. This allows the unit to produce more heat at low air temperatures (down to -15c) than competitor products, making them the best choice for koi ponds and indooor pools which are used all year round.
  • Colour touch screen controls – provides easy to use operation and programming of the unit. The colour display shows a graph of the running speed of the unit as well as information such as water inlet and outlet temperatures, ambient air temperature, current water temperature etc
  • Programmable temperature accuracy to +/- 0.5c (or down to +/- 0.1c). This makes the Thermotec Inverter ideal for koi ponds  or where more accuracy is required over the temperature variance above and below the desired set point. No external thermostat is required.
  • Electronic gas pressure sensor – allows the unit to more accurately control the compressor and fan speed resulting in higher efficiency and lower running costs
  • Unique wifi platform allows remote support for the product if requried. Our technicians can check all settings and monitor performance of the heat pump remotely to provide you with the highest level of support and the fastest issue resolution.


Thermotec-inverter-Pro-pic3 swimming pool heat pump

4. What size heat pump do I require for my pool?

The sizing guide for a covered pool is:-

Recommended Max Pool Volume
Absolute Max Pool Volume
Thermotec Inverter Horizontal 9kw9kw30m345m3
Thermotec Inverter Horizontal 12kw12kw
Thermotec Inverter Horizontal 17kw17kw
Thermotec Inverter Horizontal 20kw19.5kw
Thermotec Inverter Horizontal 24kw24.2kw
Thermotec Inverter Vertical 29kw28.6kw
Thermotec Inverter Vertical 34kw34kw109m3136m3
Thermotec Inverter Vertical 34kw (3-phase)34kw109m3136m3

5. The sizing guide for koi ponds is:-

For a koi pond that is heated all year round with a winter temperature of around 12c and a summer temperature of around 20-22c, we recommend the following sizing:-

Pond Sizing Guide
Max Pond Volume
Thermotec Inverter Horizontal 9kw4500 gallons
Thermotec Inverter Horizontal 12kw6000 gallons
Thermotec Inverter Horizontal 17kw
7500 gallons
Thermotec Inverter Horizontal 19.5kw
9600 gallons
Thermotec Inverter Horizontal 24kw
11,600 gallons
Thermotec Inverter Vertical 29kw
13,800 gallons
Thermotec Inverter Vertical 34kw
19,900 gallons
Thermotec Inverter Vertical 34kw (3 Phase)19,900 gallons

(Note: This assumes that the pond is covered in winter and that a temperature of +12c is to be maintained over winter)

For more information on using a heat pump on a koi pond, please see our Koi Pond Heating Guide page. This includes customer videos showing a Thermotec Inverter heat pump being installed and running on a koi pond


(Please note this picture shows the old colour casing)

All sizes of Thermotec Inverter heat pumps are available for standard single phase power (ie 220v to 240v) to suit most properties

For koi ponds the Thermotec Inverter range can be programmed to give a temperature control accuracy (swing) of +/- 0.5c or less without requiring a separate external thermostat.

Note: When using a heat pump to heat a koi pond, a backup heater should also be installed to provide additional heat in extremely cold weather and in the rare event that the heat pump does not function. A minimum pond water temperature of +8c is required in order for the heat pump to start.


Thermotec-inverter-Pro-pic2 swimming pool heat pump

6. COP And Performance

By using the latest inverter technology, the Thermotec Inverter can out perform traditional on/off type heat pumps as well as many other inverter driven models.

Even as the outside air temperature falls, the Thermotec Inverter will still perform well, delivering heat to your pool.

The Thermotec Inverter heat pumps can work well with outside air temperatures as low as -15c

The COP (Coefficient of Performance) is the ratio of the amount of heat (in kw) that the heat pump delivers to your pool compared to the electricity that the heat pump uses (in kw)

By using the latest inverter technology, the Thermotec Inverter has COPs up to 13.6. This means that in these conditions, 1kw of electricity consumed by the heat pump will output 13.6kw of heat to your pool !

Themotec Inverter Heat Pumps COP Ratings

Thermotec Inverter 20kw (Please note this picture shows the old colour casing)

7. Extremely Quiet Operation

The Thermotec Inverter range work very silently thanks to a unique internal ventilation system and the inverter technology.

Both the fan and compressor automatically adjust their speed to match the pool heat demand, therefore once the pool is up to temperature, the unit can operate with reduced power consumption and noise.


8. Colour Touch Screen Controls

The Thermotec Inverter have a unique 5″ colour backlit touch screen control/display panel

This provides easy to use controls

Themotec Inverter Heat Pumps Colour display

The display will show:-

  • The current pool water temperature
  • The mode (e.g. heating or cooling)
  • If the timer function has been set
  • If the fan is operating
  • The current time and date
  • The outside ambient temperature
  • If there is a fault, a fault code is displayed to explain the problem

In addition, the display can show:-

  • A graph of the temperature of the pool over time so that you can see how the pool temperature is being maintained by the Thermotec Inverter heat pump
  • A graph of the power consumed by the heat pump over time

The colour display is backlit making it easy to read in low light conditions and also in bright sunlight


9. Wi-Fi Control

The FREE Wi-Fi module allows the Thermotec Inverter Pro to be monitored and controlled from a smartphone or any internet web browser.

There are two versions of the wifi module:-

thermotec inverter wifi modulenew-wifi-module-with-4-leds-pic2

 Wifi Module with 1 LED (Before Aug 2020)

Uses the Inverter Temp App

 Wifi Module with 4 LEDs (After Aug 2020)

Uses the Aqua Temp App

The Aqua Temp  App is available for both Android and iPhone

The Wi-Fi module simply connects to the heat pump via the supplied Y-cable

The module is then joined to your wi-fi network to allow it to communicate with the internet

The wifi module also allows HeatPumps4Pools to provide remote monitoring and support of your heat pump with the ability to change any settings if required. This greatly enhances the speed and efficiency of our technical support.

The Aqua Temp app can then be installed into your smart phone to give full remote control and monitoring of your pool heat pump.

aqua-temp-appUsing the app you can:-

  • Turn the heat pump on and off
  • See the current pool water temperature
  • Alter the desired pool set temperature
  • Set the timer
  • Change the mode of the heat pump from heating, cooling and auto modes
  • Put the heat pump in and out of silence mode (e.g. for night-time use)
  • Show the weather temperatures and information
  • Display any error codes and messages

By entering a password, more detailed information can be seen including:-

  • Incoming and outgoing water temperatures
  • Compressor speed
  • Fan speed
  • Running current
  • and much more….
The Thermotec Inverter Mobile Phone App

Note: A a wifi signal is required at the location of the heat pump in order for the wifi module to be able to connect to your wifi.

Please test the strength of the wifi signal eg with a laptop or your smart phone before purchasing the wifi module.

If you do not have a wifi signal at the heat pump’s location, then you can either:-

  1. Use a wifi signal extender to boost the signal in the area of the heat pump
  2. Use power LAN adaptors plugged into mains sockets in the house and the pool shed. You can then connect a wifi extender to the powerlan adaptor in your pool shed to deliver wifi to the wifi module.
  3. Purchase the Thermotec Inverter 3G/4G Mobile Data Module (DTU) which uses the mobile data network

Please Contact Us if you need assistance with the wifi configuration

Please also see the YouTube video and user manual for the Wi-Fi module below for more information and installation instructions

10. Thermotec Inverter 3G/4G Mobile Data Module (DTU)

If you do not have wifi coverage where the heat pump is located, we also have a 3G/4G mobile data module


This module connects to the 3G/4G mobile data network and allows the heat pump to be controlled using the Aqua Temp app on a smartphone

It is ideal for locations where wifi coverage is not available where the heat pump is located.

The module includes a SIM card primarily for the EE (Orange) network but it can work with all mobile networks within Europe

It includes enough data for at least 5-years of continuous use (and can be renewed afterwards)

The unit is very easy to install

It is IP68 waterproof rated and can be installed on the outside of the heat pump case

Click Here for more details on the 3G/4G Module

11. Specifications

Thermotec Inverter Pro SpecificationsThermotec Inverter Pro Specifications

Thermotec Inverter Pro Case Sizes

Thermotec Inverter Pro Case Sizes

Thermotec Inverter Pro Case Sizes


Please also see the Specifications tab at the top of the page


(Please note this picture shows the old colour casing)

12. Winter Cover and Mounting Feet Included

The Thermotec Inverter horizontal range of heat pumps come with:-

  • 2 x Water connection unions (with 50mm glue socket outlets – 1.5″ adaptor bushes available as an option)
  • 1 x Basic Winter cover (heavy duty winter cover available as an option – see below)
  • 4 x Rubber mounting feet (heavy duty mounting blocks available as an option – see below)


13.Optional Extras:


Wi-Fi Controlaqua-temp-appSee section 7 above
Heavy Duty Mounting Feet Thermotec-Inverter-Horizontal-rear.jpgThese heat pumps come with rubber mounting feet (see photo above).

Alternatively you can purchase these heavy duty Mounting Feet.

These raise the unit off the ground by approximately 100mm, and also help to reduce vibration.

Please see our Mounting Feet and Slabs section for more information.

Bypass Kit Please see our Bypass Kits section section for more information.
Winter Cover The unit comes with a lightweight winter cover, however we offer a heavy duty cover which will give you added and extended protection against the winter weather

Please see our Winter Cover section section for more information.

Remote Display KitThe Remote display kit allows the digital display panel to be located away from the heat pump. The kit includes a 20m cable and a mounting box for the display.

It is also possible to have two displays operating with the Thermotec Inverter range.

Click here for details of the remote display kit

Plug and Play Cable KitHeat pump plug&play-cable kitWe offer a plug and play cable kit, this allows the heat pump to be plugged into a standard 13A outdoor socket

For heat pumps with input power up to 3kw or 13A

Please see our Plug & Play Cable Kit section for more information.

14. Installation

Installation is straightforward. We can provide advice on installing your heat pump. We can also offer an installation service if required.

We recommend that a bypass is installed to allow the heat pump to be drained in winter if not in use. We sell bypass kits if required.

Please see our Installation Tips pages for information on how to install your heat pump. Our Photo Gallery also has photograph examples of pool heat pump installations and please also see the FAQ pages for more information

Please contact us for further advice

15. Availability

The range of Thermotec Inverter pool heat pumps are now in stock in the UK and can be shipped to any UK address on a 1 – 3 day delivery service.

16. Delivery

The price includes FREE UK delivery.

We can ship the Thermotec Inverter heat pumps to any country. Please contact us for a shipping quote.

17. Warranty

The Thermotec Inverter heat pumps come with a 3-year parts & labour warranty on all components and 5-year warranty on the compressor and heat exchanger:-

  • 3-year parts & labour warranty on all components
  • 5-year warranty on the compressor and heat exchanger (parts only after year 3)
  • UK: 3-years parts and labour warranty
  • Europe and Outside the UK: Warranty is parts only warranty or return to us in the UK (customer pays transport cost). If spare parts are required, they will be sent free of charge to a UK address. If they are to be shipped outside the UK, the customer pays the international shipping cost

We recommend that you retain the pallet and packaging that the heat pump was delivered with in case you need to return the unit to us for repairs under the warranty.

The warranty will not apply where the heat pump has been installed incorrectly, or has been damaged by freezing

18. Technical Support

We are happy to provide technical support for all Thermotec Inverter swimming pool heat pumps that we supply.

We hold spare parts to support all Thermotec Inverter heat pumps both during and after the warranty period

19. Product Literature

Please click the links below to download pdf brochures for these products

Thermotec Inverter Wi-Fi User Manual – Aqua Temp App – V3
Thermotec Inverter Wi-Fi User Manual – Aqua Temp App  – V2
Thermotec Inverter Wi-Fi User Manual – Inverter Temp App –  V1


Please also see the Literature tab at the top of the page for the Brochure and User Manual downloads.

20. Product Videos

Overview of the 34kw Vertical Thermotec Inverter Swimming Pool Heat Pump

Overview of the 9kw Horizontal Thermotec Inverter Swimming Pool Heat Pump

How to install the new type wifi module and Aqua Temp app for the Horizontal Thermotec Inverter swimming pool heat pumps

How to install the old type wifi module and Inverter Temp app (now replaced by the Aqua Temp app)

21. Customer Feedback

We have received many positive reviews about the Thermotec Inverter range of pool heat pumps. For example…

“Hi, I just wanted to tell you how amazing the new heatpump is. Thanks for your advice regarding it. We still have a pool that’s 30 degrees, unheard of for October.

It was a great buy.

The pool has kept a lot of young families sane during lockdown!


Jackie Hoyland (Thermotec Inverter 24kw heat pump October 2020)


To see more feedback, please see our Customer Feedback page

22. Assistance?

If you need any assistance or advice as to which model would be best for your pool, please email us or call us on 01268-206560

for more information, also see our FAQs page

All items sold in accordance with our terms and conditions

For all enquiries, please contact us at enquiries@heatpumps4pools.com



Thermotec Inverter Pro Specifications Thermotec Inverter Pro Specifications Thermotec Inverter Pro Case Sizes Thermotec Inverter Pro Case Sizes Thermotec Inverter Pro Case Sizes

R32 Models – (From October 2020)


R410a models – (Before Oct 2020)

Themotec Inverter Heat Pumps Specifications

Electrical Requirements (R32 models – after Oct 2020)

ModelMax CurrentBreaker SizeRuns from 13A UK Plug?Min Cable Size mm2
20kw17.3A25A Type CNo4mm2
24kw23A25A Type CNo4mm2
24kw 3-phase10.6A (per phase)16A Type CNo2.5mm2

Electrical Requirements (R410a models – prior to Oct 2020)

ModelMax CurrentBreaker SizeRuns from 13A UK Plug?Min Cable Size mm2
17kw13.96A16A Type CNo2.5mm2
20kw21.7A25A Type CNo4mm2
24kw24A25A Type CNo4mm2
24kw 3-phase10.61A (per phase)16A Type CNo2.5mm2


We accept all major credit and debit cards, Bank Transfer (BACS) and PayPal


PayPal Credit

paypal credit

For details of PayPal Credit please click here: PayPal Credit


The prices shown include FREE UK delivery for orders over £50 or £6.50 for orders under £50

We can ship to any country. Please contact us for a shipping quote.

The lead time on most items is normally on a 1-2 day delivery,  subject to availability. Please call to check availability.

Additional information

Weight70 kg

9kw, 12kw, 17kw, 20kw, 24kw


Single Phase, 3 Phase