Five key facts about heat pump water heaters


With sustainability high on the industry agenda, Ariston has invested significantly in developing its renewables offering, as demonstrated by the launch of the company’s new Nuos Plus Wi-Fi heat pump water heaters.

But what exactly are the benefits of these state-of-the-art products? Victoria Gutierrez, Head of Marketing at Ariston, explains.

1. They use electricity to extract heat from the air

Instead of generating heat directly, heat pump water heaters work on the same principle as a typical fridge-freezer – but in reverse! In other words, they take the heat from the surrounding air and then transfer it (at a higher temperature) to warm up water in either a storage tank or cylinder.

Indeed, the products are similar to unvented cylinders, although ducting is used to draw air in and let the exhaust air out. Quiet, clean and easy to operate, these units are already proving popular in properties in off-gas areas – although they are suitable for homes of all ages, whatever their location, as well as light commercial projects.

2. They are highly efficient

Modern heat pump water heaters such as Nuos Plus Wi-Fi utilise all the benefits of fast and efficient hot water delivery, while also boasting exceptionally high coefficients of performance (COPs) up to 3.14. This, coupled with an A+ ErP rating, makes them the most efficient on the market – and an excellent alternative to traditional electric storage water heaters.

Thanks to this high level of sustainability, heat pump water heaters allow more properties (particularly those in off-gas areas) to benefit from renewable technology, without requiring investment in multiple products.

3. They are economical to run and reduce energy bills

Specifically designed for producing hot water alone, Nuos Plus Wi-Fi heat pump water heaters can operate at air temperatures as low as -10°C. In addition to helping reduce household utility costs, units can also be sited with ease, usually in utility rooms, garages, out-buildings and specially constructed compartments or cupboards.

Heat pump water heaters also boast substantial economic savings when compared to other products in the sector. In contrast to other types of water heating technology, these units utilise extended operating temperature ranges, while achieving exceptional energy savings of up to 80% when analysed against traditional cylinders with similar capacities. Plus, these products are significantly lower in price than solar-powered DHW systems.

4. Keeping control is simple

Controllability is now an essential part of all heating and hot water products – and the Nuos Plus Wi-Fi takes this to another level, with brand new operating modes, including daily and weekly programming options, as well as ‘I-Memory’, which learns water usage habits in order to automatically create a tailored, intelligent pre-heating schedule.

In addition, controllability is further enhanced by three different modes: ‘Green’ mode ensures the only heating source is the heat pump itself, limiting the temperature to 62°C maximum. ‘Comfort’ mode provides faster reheat times, as the heating element assists or replaces the heat pump, thereby replenishing the water as quickly as possible. Finally, ‘Boost’ mode activates the heat pump and heating element at the same time until the desired temperature is achieved.

Furthermore, features such as anti-legionella and anti-freeze functionality prevent bacterial growth, while maximising protection during the winter months.

5. They are smarter than standard water heaters

Advances in smart technology have led to modern water heating products benefitting from the latest in Wi-Fi connectivity. Nuos Plus Wi-Fi maximises this functionality, thanks to the sophisticated Aqua Ariston Net app, which lets the user shuffle through the various modes from their smartphone – and ensure a hot shower is always available at the perfect time.

Comprehensive research and development have also revealed the combination of the connectivity of Aqua Ariston Net with the Nuos Plus heat pump water heater can save up to 25% on annual energy bills. This is a result of real-time energy consumption analysis and reports, which monitor exactly how much water and energy is being used.