Ariston Clas Net One Combi Boiler

The Ariston Clas Net One Combi is a top performing boiler that’s designed to suit even the most demanding situations.

Ariston Clas Net One Combi

Ariston’s Clas Net One Combi is the brand’s flagship product that now performs better and more efficiently than it has ever done before. It also happens to come with a market-leading warranty and a whole host of impressive features and technology to enhance performance. As this boiler has been tested and certified for safety, quality and usability by TUV Rheinland, you can be confident that you’ll be investing in a reliable and top performing appliance when you purchase the Ariston Clas Net One Combi. 

How Much Does this Boiler Cost?

Available with an output of 24, 30 or 38kW and hot water flow rates of 10.4, 12.5 or 15.5 respectively, the Ariston Clas Net One Combi will set you back anything between £1,315 and £1,570. Of course, the amount you’ll need to fork out will all depend on which output you need, with the 38kW version being the most expensive of the three sizes. Then you have to factor in the cost of installation, which could be anything from £1,500 to £1,800.

How will I know if this Boiler is Suitable for My Home?

Ariston offers three different outputs, so there’s a Clas Net One Combi to suit properties of all sizes. And as the boiler doesn’t need separate water tanks or a cylinder to supply hot water on demand, it doesn’t take up much space. The only trouble with it being a combi is that it isn’t the best choice for properties with more than one bathroom because combi boilers don’t cope very well with demand for hot water from multiple taps or showers at the same time. We should also point out that an LPG conversion kit is included in the box, so the boiler is ideal if your home is in either an on or off-mains gas area.

To ensure you choose the correct boiler type and size for your household, you need to get a Gas Safe engineer to assess your property and requirements.

Is it a High Efficiency Boiler?

It certainly is. The Ariston Clas Net One is A-rated for efficiency and is an Energy Saving Trust recommended boiler. So, if you’re about to replace a rather old boiler with this one, you should save a large chunk of money on your energy bills and even reduce your carbon footprint. The boiler features an enhanced Xtratech single coil heat exchanger to improve energy efficiency, as well as an Auto Function that enhances both performance and efficiency. 

Does this Boiler have a Good Range of Controls and Features?

Well, we’ve already mentioned the new Xtratech heat exchanger to help keep emissions and energy bills low but this boiler has lots of other great features too. For example, it comes with an improved silencer and the latest soundproofing technology to ensure the boiler runs quietly. The Ariston Clas Net One Combi also has a built-in Auto Function, which basically monitors the ideal temperature and automatically chooses the right output to optimise efficiency. Plus, it comes with a Comfort Mode which makes sure the boiler delivers hot water almost instantaneously whenever needed. What’s more, it has a clear display panel with intuitive buttons and is compatible with Ariston’s latest optional wired and wireless controls.    

How long is the Warranty on this Boiler?

The boiler comes with a 12-year parts and labour warranty as standard. This is incredibly generous compared to the warranties offered by other well-known boiler brands. 

Summary of Important Information

  • Priced between £1,315 and £1,570
  • Heating output of 24kW, 30kW or 38kW
  • Hot water flow rate of 10.4, 12.5 or 15.5 litres per minute
  • Dimensions of 745mm (H) x 400mm (W) x 385 (D)
  • Uses gas or LPG as its fuel source
  • A-rated for efficiency
  • 12-year warranty as standard

Pros and Cons

There really isn’t anything not to like about this boiler, although we have noticed that Ariston has just an average rating on Trustpilot. The feedback on there is pretty mixed, so it might be worth checking out the reviews for yourself. 


  • Ariston boilers have a good overall Which? score of 64%
  • Suited to small, medium and large-sized homes
  • No need for separate cylinder or loft tanks
  • Easy to install, use and service
  • Xtratech stainless steel heat exchanger – maximises longevity, reliability and efficiency
  • Auto Function – enhances boiler performance and aids energy efficiency
  • Comfort Function – boiler can deliver hot water almost instantaneously
  • Improved silencer and the latest soundproofing technology – quieter running
  • Provides maximum energy efficiency – reduce fuel bills and carbon emissions
  • Compatible with a range of Ariston controls – improves efficiency and performance
  • TUV Rheinland tested and certified – safety, quality and usability
  • Works with LPG if required – perfect for properties off the gas grid
  • 12-year warranty


  • Ariston has an ‘average’ Trustpilot rating – correct at the time of writing in May 2019