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:
- 95% AFUE high-efficiency rating
- 110,000 BTU/hr heating input
- Up to 199,000 BTU/hr DHW input
- 8.5:1 turndown ratio for heating
- 15:1 turndown ratio for domestic hot water
- Smart controls with backlit LCD and Setup Wizard
- Dual stainless steel heat exchangers
- Field convertible between natural gas and propane
- Built-in zone pump and zone valve connections
- Compact, wall-hung design with quiet operation
- Supports 2" or 3" direct venting
Applications:
- Residential space heating and hot water
- Homes with simultaneous multi-fixture usage
- Natural gas or propane fuel systems
- Installations requiring compact, high-efficiency units
- New construction or retrofit boiler replacements
- Indoor wall-mounted applications with venting flexibility
Aim high with Navien...
High efficiency, High output, High performance, all in one compact combi
- Highest DHW maximum BTU’s in residential combi-boilers...up to 210,000 per hour
- Highest DHW flow rate @ 70°F rise...up to 5.4 GPM
- Highest number of BTU sizes for the North American residential combi-boiler market
- Highest residential combi DHW TDR...15:1 for all models
- Highest residential combi heating TDR... up to 11:1
- Highest number of built-in zone controls for valves or pumps... up to three
- Highest full lineup 2" PVC venting lengths... up to 65 feet
- Highest number of cascade capable units with NPE tankless water heaters... up to 15
- High altitude certification... up to 10,100 feet (NG or LP)
- Lowest minimum fire BTU for residential combi-boilers... as low as 10,700
New Navien NCB-H...the complete combi package and no comprimises
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.

COMPARE these advantages and see why NCB-H combis are the right fit for small and large homes
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 Dual stainless steel heat exchangers for heating
Durable stainless steel heat exchangers resist corrosion, resulting in longer life and improved heat recovery from flue gases for superior efficiency.
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 Up to 5.4 GPM @ 70°F temperature rise for DHW
Separate stainless steel flat plate heat exchanger for DHW creates the lightest flow rates for any combi-boiler in the industry.
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 Dual Venturi and field gas convertibility
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.
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 Easy access to DHW module and valves
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.
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 Low noise levels
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.
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 TDR 15:1 for DHW and up to 11:1 for heating
The sophisticated gas flow control system provides a high turndown ratio, reducing energy waste and excessive boiler cycling and enhances temperature control for DHW.
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Dual Stainless Steel
Heat Exchanger
Designed for exceptional
heating performance and longevity
Heating up to
150,000
BTUs per hour
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Built-in DHW module now with
higher performance
Navien’s NCB-H generates enough hot water to run up to 3 showers and a dishwasher at the same time.


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

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