combi crossover

The next-generation boiler

More than just a boiler and more powerful than Combi boilers, the Combi Crossover is a new range of high-performance boilers that delivers efficient hot water to meet the needs of the busiest households.

Thanks to Navien ON technology, the ground-breaking Combi Crossover boilers have the power and performance of a system boiler and the advantages of a Combi boiler without the cylinder, eliminating slow heat-up times and low flow rates.

Backed by the efficiency and intelligence of Navien’s pioneering technology, expert technical support and an up to 12-year warranty, the Combi Crossover is the ideal choice of boiler.



By putting hot water first, our innovative ON technology removes the fluctuation between hot and cold by providing quality, consistent and efficient hot water. With Navien ON, the possibilities are endless.


The award-winning NCB700 ON Combi Crossover is the first of its kind, with the capability to deliver hot water to three bathrooms simultaneously. Even in the largest properties, the NCB700 ON maximises the recirculation of hot water to reduce water wastage by saving up to 7,787 litres per year. This helps increase efficiency, saving up to 38% on average per year on energy to keep your bills down. All this, without the hot water cylinder, making the NCB700 ON a great space saving boiler.


Featuring the same ON technology, the NCB500 ON is an energy-saving Combi Crossover boiler that provides hot water with no changes to temperature or flow rate to meet high demand while increasing energy efficiency.




H2 20

A future-proof hydrogen-ready boiler that prioritises hot water performance.

Combi Crossover boilers are hydrogen-ready with an ErP A+ rating when used with Navien’s Smart Plus Controller. By prioritising hot water performance, the Combi Crossover range represents a more economical choice when compared to regular boilers.

Up to 12-year warranty

All Navien boilers are engineered for reliable long-term performance. If a boiler is serviced regularly and breaks down within the warranty period, it’s our responsibility to repair or replace it. All our boilers come with a hassle-free warranty of up to 12 years, which includes the repair and ongoing support of your boiler.

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