ATAG ATAG I40S 40kW System Gas Boiler

ATAG I40S 40kW System Gas Boiler
Total Cost
Manufacturer ATAG
Boiler Model ATAG I40S 40kW System Gas Boiler
Condensing boiler? Condensing
Energy Efficiency Rating 94%
Energy Band A Rated
LPG model/Conversion kit Yes
Manufacturer Warranty Up to 14 Years
Heating Output 38.8 kW
Wall Mounted or Floor Standing Wall Mounted
DHW Flow Rate N/A
Total Cost
ERP Rating A Heat A Water
Hot Water Max Output

ATAG I40S 40kW System Gas Boiler review

The ATAG I40S boiler comes with a standard 10-year warranty, and options for up to 14 years when they are professionally installed by ATAG Selected Partners. Renowned for their energy efficiency, these domestic boilers are built to last and provide you with years of low-cost heating.

ATAG, a Dutch company that designs and manufactures boilers, is based in Holland. They claim to have established the highest standards of engineering excellence and energy efficiency in the world over that period. ATAG manufactures a variety of gas boilers, including a combi boiler, system boiler, and regular boilers in various sizes.

ATAG boilers are made from high-quality brass and stainless steel components. ATAG boilers are designed to incorporate what ATAG calls their revolutionary iCon heat exchanger, which offers unrivaled performance and efficiency levels.

Why choose the ATAG I40S system boiler?

You’ll choose an ATAG iS boiler and enjoy its energy efficiency. These boilers are also easy to use.

The ErP pump is what makes our boilers stand out. The ErP pump controls the heat from the boiler and ensures that your boiler is as efficient as possible. This will help you save money each year.

ATAG iRange boiler meets European standards (CE) and is closed, condensing, and modulating heating boiler. The manufacturer can provide a declaration of conformity.

The boiler’s efficiency is high, and radiation convection losses and standby losses are low. The boiler has a high-efficiency rating of >88% SEDBUK 2009. This is because it emits noxious substances at levels far lower than the standards.

ATAG 40kW system boilers for homes in the UK

Traditional system boilers have an unvented hot water cylinder, which increases the hot water capacity. It is a space-saving solution because the controls and pump are all contained in the boiler casing.

  • To fit in kitchen cabinets, a model measuring 275mm (deeper) is available
  • Standard warranty of 10 years, with options for up to 14-years
  • You can control the system using your smartphone via the ATAG ONE Zone smart controller or Tado V3+ smart Controller
  • ATAG iCon stainless-steel heat exchanger – with its lifetime replacement guarantee
  • LCD Display displays detailed fault codes for faster, more precise boiler diagnosis
  • Compatible with ATAG iSteel cylinders range & 3 port valve kit
  • For increased efficiency, built-in anti-cycling function
  • Condensate and pressure relief valve outlet pipes are less expensive.
  • Compatible with both solar thermal hot water systems as well as the ATAG iSteel twin-coil cylinder range
  • Standardly supplied with a fixing jig, for rear pipe up behind the boiler
  • Pump for improved efficiency and low electrical consumption, factory-fitted ErP-ready pump

Who are our fitters?

We use our own Gas Safe installers and the best installers the UK has to offer. Every single one is Gas Safe registered and has been thoroughly vetted.

Get my fixed price now

Get a great price on a Which? Best Buy boiler online in minutes

We have all the best combi boilers in the UK, plus you can see the cost of a new boiler online in under 20 seconds for your peace of mind.

Here's whats included with your full Gas Safe installation boiler quote from Boiler Central.

Don't just take our word for it...

Read More Reviews
Next-day fitting available until 2pmGet a quote now >