Condensing gas boiler MCR4 24/29 MI dual function 7857048

Wall-mounted condensing boiler that runs on 20% hydrogen gas – without additional modifications

The MCR4 24/29 MI boiler is designed to work with hydrogen-blended gas – it requires no modifications to operate safely and efficiently. The Gas Adaptive system automatically controls combustion, adjusting parameters to the type of gas: E, Lw, Ls, or propane/butane. If you plan to use Ls gas, a conversion kit will be required – but that is the only thing you need to add yourself.

Design that facilitates installation and maintenance

Dimensions of 395 x 700 x 285 mm and a weight of 28.5 kg mean the boiler fits easily even in tight spaces – and its lightness facilitates transport and installation. The stainless steel toroidal heat exchanger not only ensures a long service life (5-year warranty) but also allows for an efficiency of up to 105.8% at full load. This is not a theoretical value – it results from actual operation under condensing conditions.

The brass hydraulic module includes an A-class modulated pump (EEI < 0.23), a plate heat exchanger (also made of stainless steel), a 3 bar central heating safety valve, and a flow limiter – all in one block. No external components need to be added to the basic system.

Flue gas discharge? You have a choice

You don't have to choose between a traditional chimney and a modern system – the boiler supports both. You can connect it to:

• a traditional chimney (B23p and C93 certification),
• a coaxial flue (C10, C13, C33),
• a pressurized collective flue system (C43P),
• a distributed system (C53).

A Ø60/100 mm fitting is included in the set – you don't need to buy it separately. The non-return valve in the air-gas module allows for operation even under flue gas pressure – which means there are no problems with discharge in installations with long ducts.

Control that works like an app

The E-Pilot console is not just a screen – it is an interface with weather compensation. Simply add an AF60 outdoor temperature sensor (optional) so the boiler can automatically regulate power based on weather conditions. You can also connect a Smart TC thermostat – and control the entire system via your phone. The app works on Android and iOS, shows errors in real-time, and allows for remote monitoring.

If you have an additional heating circuit (e.g., underfloor heating), you can install the SCB-17B board directly in the boiler – there is no need to mount a separate controller.

What else is worth knowing?

• DHW production at Δt=35°C: over 11 liters per minute – sufficient for a multi-room house.
• NOx emission below 14 mg/kWh – category 6, the lowest possible.
• Seasonal space heating efficiency: 94%.
• Noise level: 50 dB(A) – as quiet as a standard refrigerator.
• 8 liter expansion vessel built-in – no external one required.
• Power supply: 230 V / 50 Hz; IPX5D protection rating – moisture resistant.

There are no "magic" functions here. This is solid equipment for specific installations – where you need control, efficiency, and flexibility.