• Get the best quotes, fast!
  • Over 5,000 engineers across the UK
  • Gas Safe registered engineers

Need a New Boiler?

What work do you require?

Or do you require a boiler repair?

Get THE Best Deal

by quickly comparing 3 FREE quotes

  • Next day installation
  • Quotes from local engineers
  • 1.9 million quotes in 10 years
  • Save up to £500 on installation

The smarter way to find approved heating engineers

Excellent 4.8 out of 5 Trustpilot

Stay Safe.
Always use a Gas Safe registered engineer

ATAG I40S 40kW System Gas Boiler

ATAG I40S 40kW System Gas Boiler Boiler
Typical Price (inc VAT)
£N/A
Typical installation Cost (inc VAT)*
£500 - £1000
Sundries (Filter, Flue, etc)
£300
Make ATAG
Model I40S 40kW System Gas Boiler
Is Condensing Condensing
Efficiency Rating 94%
Band Rating A Rated
LPG Compatible Yes
Standard Warranty Up to 14 Years
Central Heating Max. Output 38.8 kW
Mounting Wall Mounted
Flow Rate N/A
Typical Price (inc VAT) £N/A
Typical installation Cost (inc VAT)* £500 - £1000
ERP Rating A Heat A Water

* This is a guide price for a straightforward, like-for-like boiler replacement. Installation costs will vary dependent on work required.

Get your best deal

Quickly compare 3 FREE quotes

  • Quotes from local engineers
  • Get quotes today, installed tomorrow
  • Finance options available
  • Save up to £500 on installation
Get Quotes Now It only takes 30 seconds
0330 808 0405
Call us to get quotes

We will get you the best deal!

0330 808 0405
4.7/5 out of 27,014 reviews

1,8 million quotes provided in 10 years

Product Description

The IS40 system boiler is a wall-mounted, gas fired appliance from ATAG. The compact dimensions of 700x440x355mm make it perfectly suited to suit homes where space may be limited while the high output of 38.8 kW ensures it can meet a high demand for hot water including multiple bathroom homes.

Smaller outputs are available (starting at 15kW) for homes with a lesser demand for hot water.

ATAG system boilers include an inbuilt ErP pump which delivers an A rated 94% energy efficiency level. This pump helps to control heat loss to ensure your boiler is as energy efficient as possible and help to save you money. To improve the efficiency even further you can combine the boiler with an ATAG iSteel hot water cylinder. It can also be used with the ATAG One controller and has a 3 port valve kit.

Other key features include user friendly controls to give you maximum control of the boiler and the unique iCon heat exchanger which has a lifetime replacement guarantee. This highly reliable unit is ideal for heating systems which include a hot water storage cylinder as it directly heats your central heating and produces hot water for a storage cylinder. Most of the important parts of the hot water and heating system such as the pump and expansion vessel are built in on a system boiler making it quicker and cleaner to install. This also means you get a faster response to demand for heating and hot water and you don't need to have a feed and expansion tank in the loft.

Available with an extensive 10 year warranty as standard, ATAG also give you the option of extending this period to 14 years when certain terms are met. To get a longer warranty, the installation must include an Adey Atom filter, ONEZone smart controller and water treatment pack.

Get your best deal

Quickly compare 3 FREE quotes

  • Quotes from local engineers
  • Get quotes today, installed tomorrow
  • Finance options available
  • Save up to £500 on installation
Get Quotes Now It only takes 30 seconds
0330 808 0405
Call us to get quotes

We will get you the best deal!

0330 808 0405
4.7/5 out of 27,014 reviews

1,8 million quotes provided in 10 years

Need a new boiler?

Get FREE no-obligation quotes now!

Find approved boiler engineers
in your area.

Begin your search by entering your postcode below.

Or select your region from the list and start your search