combi crossover

The next-generation boiler

Introducing the Combi Crossover from Navien UK, the next generation of boilers. As part of the NCB ON range, the Combi Crossover boilers have the power of high-performance system boilers with the cylinder-less advantages of compact Combi boilers.

By putting hot water first, with rapid hot water and consistent temperature features, the Combi Crossover range offers a new approach to home heating to give your clients the best boiler for meeting all their hot water needs. The recirculation of domestic hot water significantly reduces hot water and energy usage, helping keep customer bills down. This is all possible without the need for a hot water cylinder, making for faster installations and a cost-effective option for your customers.



The NCB ON range has completely reinvented what is possible in larger homes, boasting greater efficiency, quality performance and consistent hot water. The state-of-the-art water adjusting valve maximises hot water comfort and alerts the user when the water goes above 35oC.


The first of its kind, the NCB700 ON Combi Crossover is more than just a combi boiler. The hydrogen-ready boiler (with an ErP A+ rating when used with Navien’s Smart Plus controller), has incredible all-round performance. Including flow rates of up to 22 litres per minute, to deliver instant hot water to several outlets at the same time.

NCB700 ESA Award Winner 2022


The NCB500 ON offers hassle-free installations, with the same high-quality construction as the NCB700 ON. The energy-saving boiler can achieve hot water outputs of up to 32kW and has an ErP efficiency rating of 93%, guaranteeing more affordable heating for your customers.




H2 20

An efficient boiler that priorities hot water performance

The Combi Crossover boilers are part of the NCB range, Navien’s energy-efficient and future-proof of range that prioritises hot water performance. We are committed to supporting the UK government’s Net Zero carbon targets, proven by our recent innovations, that gives the Combi Crossover an A+ energy rating and are 20% hydrogen blend ready.

Navien UK is committed to revolutionising how the industry thinks about boiler technology alongside our commitment to quality for our valued installers. The Combi Crossover is just the start of our next generation of boilers.

Up to 12-year warranty

Backed by the efficiency and intelligence of Navien UK’s pioneering ON technology, expert technical support and available with up to 12-year warranty, you give your customers complete peace of mind over the longevity and reliability of the boiler.

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