ATAG Q25CR 25kW Natural Gas Combi Boiler

ATAG Q25CR combi boiler

The ATAG Q25CR Natural Gas Combi Boiler is a wall-mounted condensing boiler designed to provide central heating and domestic hot water from one appliance. Part of the ATAG QR Series, it combines a stainless-steel heat exchanger, an integrated hot-water buffer, built-in electronic controls and a circulating pump.

With a nominal heat-input rating of 25kW, the Q25CR is intended for suitable residential and smaller commercial heating applications where its heating capacity and hot-water performance meet the requirements of the installation.

The Q25CR includes an integrated 14-litre hot-water buffer, helping support domestic hot-water delivery without requiring a separate domestic hot-water storage cylinder in a typical combi installation.

Key Features of the ATAG Q25CR Boiler

• ATAG Q25CR natural-gas combination boiler
• 25kW nominal gross heat input
• Wall-mounted condensing boiler design
• Integrated 14-litre hot-water buffer
• Stainless-steel heat exchanger
• Built-in LMS controller with display
• Integrated circulating pump
• Two OpenTherm connection options
• Support for up to three heating circuits with suitable components
• Domestic hot-water flow of up to 10.7L/min at a 35°C temperature rise
• Compatible manufacturer-approved flue options
• Designed for central heating and domestic hot-water production
• Suitable for residential and appropriate smaller commercial installations

Confirm the precise model reference, included components, gas category and current manufacturer documentation before purchasing.

ATAG Q25CR Heating Output

The Q25CR has a nominal gross heat input of 25kW. Its useful heating output varies according to the flow and return temperatures of the heating system.

These figures describe different operating conditions. The 25kW model designation should not be confused with the useful heat output available to the heating circuit.

Select the appropriate boiler using a building heat-loss calculation and the requirements of the proposed heating system.

Domestic Hot Water and the Integrated Buffer

The ATAG Q25CR combines central heating and domestic hot-water production in one appliance. Its integrated 14-litre hot-water buffer distinguishes it from simpler instantaneous designs without hot-water buffering.

ATAG’s published UK/Ireland technical specification lists the following maximum hot-water flow rates:

A smaller temperature rise permits a higher flow rate. Actual performance depends on the incoming-water temperature, supply pressure and simultaneous demand.

When choosing a combi boiler, consider the expected use of taps, showers and baths. The published figures should not be interpreted as guaranteed real-world flow under every installation condition.

Stainless-Steel Heat Exchanger

The ATAG QR Series uses a stainless-steel heat exchanger as part of its condensing boiler design.

Condensing technology recovers heat from the combustion process. Actual operating performance depends on system temperatures, commissioning, controls, water quality, installation design and regular maintenance.

The manufacturer’s efficiency ratings should be interpreted according to their stated test conditions and calculation method. They do not guarantee a particular reduction in household energy bills.

Built-In LMS Controller and Heating Zones

The Q25CR includes an LMS controller with a display and integrated boiler-management functions.

The QR Series supports two OpenTherm connection options and can accommodate up to three heating circuits when configured with suitable system components, including compatible mixing valves where required.

Heating zones can help manage different areas independently. The installer must verify the control arrangement, wiring and hydraulic design for the intended application.

Wall-Mounted Installation and Flue Options

The ATAG Q25CR has a wall-mounted design intended for installation with compatible pipework, a suitable gas supply, electrical connections and an approved flue arrangement.

The selected flue configuration must match the installation layout and the manufacturer’s permitted system. Before ordering, confirm the mounting surface, appliance clearances, terminal location, condensate drainage and servicing access.

ATAG Q25CR Technical Specifications

Brand: ATAG
Product series: QR Series
Model: Q25CR
Appliance type: Condensing gas combination boiler
Fuel: Natural gas for the referenced UK/Ireland specification
Nominal gross heat input: 25kW
Nominal useful heating output at 80°C/60°C: 22.1kW
Nominal useful heating output at 50°C/30°C: 24.3kW
Minimum useful output at 80°C/60°C: 6.1kW
Minimum useful output at 50°C/30°C: 6.7kW
Integrated hot-water buffer: 14 litres
Hot-water flow at a 35°C rise: 10.7L/min
Hot-water flow at a 28°C rise: 13.4L/min
Heat exchanger: Stainless steel
Controller: Built-in LMS
Circulating pump: Integrated
Heating-zone control: Up to three circuits with suitable components
Installation: Wall mounted
Flue: Compatible manufacturer-approved system

Refer to the exact manufacturer’s technical sheet for current dimensions, energy-label data, product identifiers and installation limits.

Installation and Safety

The ATAG Q25CR is a gas-fired appliance and must be selected, installed, commissioned and serviced by appropriately qualified professionals in accordance with the manufacturer’s instructions and the regulations applicable to the installation country.

Before purchasing, confirm:

• Required heating output and design temperatures
• Natural-gas compatibility and permitted gas category
• Available gas pressure and supply capacity
• Domestic hot-water demand
• Flue route and termination requirements
• Condensate drainage
• Electrical connections and control requirements
• Mounting and servicing clearances
• Product certification and local service support

The ATAG technical manual consulted identifies the relevant version as intended for the UK and Ireland. Before supplying it elsewhere in Europe, confirm the product’s certification, gas category, pressure requirements and local installation compatibility.

Frequently Asked Questions

What is the ATAG Q25CR?

The ATAG Q25CR is a wall-mounted condensing natural-gas combination boiler designed to supply central heating and domestic hot water.

Is the Q25CR a 25kW output boiler?

Its nominal gross heat input is 25kW. Useful heating output is approximately 22.1kW at 80°C/60°C and 24.3kW at 50°C/30°C.

How much hot water does the Q25CR provide?

ATAG’s published specification lists 10.7L/min at a 35°C temperature rise and 13.4L/min at a 28°C rise. Actual delivery depends on inlet temperature, pressure and demand.

Does the Q25CR have a hot-water buffer?

Yes. The published product information lists a 14-litre integrated hot-water buffer.

Does the Q25CR include a circulating pump?

Yes. ATAG’s QR Series documentation lists an integrated pump for the combi model.

Can the Q25CR control multiple heating zones?

The QR Series supports up to three heating circuits when configured with compatible controls and components. The installer must confirm the correct system design.

Is this Q25CR model approved for every European country?

Not automatically. The referenced technical documentation identifies the UK/Ireland market. Confirm certification, permitted gas category, pressure requirements and service availability for the destination before ordering.

Who should install the ATAG Q25CR?

An appropriately qualified gas-heating professional should assess the installation, fit and commission the boiler, and maintain it according to ATAG’s instructions and local regulations.

Buy the ATAG Q25CR Natural Gas Combi Boiler

The ATAG Q25CR is an option for heating installations requiring a wall-mounted natural-gas combi boiler with integrated hot-water buffering. Before ordering from EuroFuelSupply, confirm the exact model reference, availability, included components, flue requirements, warranty terms and suitability for your destination.