4.5
Based on 1790 reviews
Based on 1790 reviews
£59.99
Easy, hassle-free returns within 30 days of receiving your order. See policy page
A fair and transparent process, with no restocking fees or hidden charges.
SSL-encrypted checkout. Refunds are issued to your original payment method.
Friendly help whenever you need it. Contact us anytime and we'll get back to you.
Payment Methods:
Navien NCB-240/110H – Condensing Combi-Boiler – 199,000 BTU DHW / 110,000 BTU HTG
The Navien NCB-240/110H is a 95% AFUE condensing combi-boiler designed to deliver both space heating and domestic hot water in one high-performance, wall-mounted unit. With a maximum heating input of 110,000 BTU/hr and up to 199,000 BTU/hr for DHW, it efficiently meets the demands of larger homes or applications with simultaneous heating and hot water needs.
This combi-boiler operates on natural gas or propane and includes advanced features such as dual stainless steel heat exchangers, a smart control interface, and built-in zone pump and valve terminals. With turndown ratios of 8.5:1 for space heating and 15:1 for hot water, the NCB-240/110H adapts efficiently to fluctuating usage demands, reducing wear and energy waste.
Features:
Applications:
Â
Navien’s innovation and technological advancements have done it again. The new NCB-H is taking combi performance to the highest levels. As the competition tries to get closer, Navien ingenuity keeps advancing their lead.

|
Durable stainless steel heat exchangers resist corrosion, resulting in longer life and improved heat recovery from flue gases for superior efficiency. |
Separate stainless steel flat plate heat exchanger for DHW creates the lightest flow rates for any combi-boiler in the industry. |
Dual Venturi system creates better combustion control and turndown ratio. Orifice conversion kit for easy field gas convertibility from NG to LP is included with every NCB-H Series combi-boiler. |
|
All components of DHW module including water feed valve, flow adjustment valve, mixing valve and 3-way valve are right behind circuit board for easy serviceability. |
Installations in or near media rooms, recreation rooms or any living areas of the house are possible with the quiet running NCB-H combi-boilers. |
The sophisticated gas flow control system provides a high turndown ratio, reducing energy waste and excessive boiler cycling and enhances temperature control for DHW. |
Â
Dual Stainless SteelHeat ExchangerDesigned for exceptionalheating performance and longevityHeating up to150,000BTUs per hour |
![]() |
Â


Â
For increased domestic hot water flow demand, the NCB-H can be cascaded and common vented with up to 15 NPE tankless water heaters

Â
ZNS
Based on 1,790 reviews