Navien NCB-240/110H Gas Combi-Boiler is a high-efficiency, space-saving solution designed to provide both domestic hot water and hydronic space heating in a single unit. With advanced condensing technology and a robust 199,000 BTU input, this combi-boiler delivers reliable performance while maximizing energy savings. Ideal for residential or light commercial applications, the NCB-240/110H offers consistent hot water and heating without the need for a separate water heater.
Homeowners and contractors looking for a reliable, energy-efficient, and compact solution for both heating and hot water will find the NCB-240/110H an excellent choice. It reduces installation complexity, lowers energy bills, and ensures comfort for your household or commercial space.
Navien NCB-240/110H is a high-performance, condensing combination boiler that delivers both space heating and on-demand domestic hot water within a single, compact unit. Offering an input capacity of 240,000 BTU/h for hot water and 110,000 BTU/h for space heating, this combi-boiler provides reliable performance and exceptional energy efficiency for modern homes.
Exceptional Energy Efficiency: Utilizing advanced condensing technology, the NCB-240/110H achieves an AFUE rating of up to 95%, capturing heat from exhaust gases and reducing energy waste. This results in lower utility bills and a more eco-friendly heating solution.
Space-Saving Wall-Mount Design: Perfect for apartments, townhouses, or larger residences, this wall-mounted combi-boiler eliminates the need for separate heating and water systems, freeing up valuable space while maintaining consistent performance.
Intelligent Controls for Optimal Comfort: Equipped with digital controls, the NCB-240/110H allows precise adjustment of heating and hot water settings. Its modulating burner adapts to real-time demand, delivering steady hot water and heating while optimizing energy usage.
Durable and Environmentally Friendly: Featuring a stainless steel heat exchanger, the NCB-240/110H provides superior durability, excellent heat transfer, and corrosion resistance. Ultra-low NOx emissions make this unit a green choice that complies with strict environmental standards.
Continuous Hot Water Supply: Designed to handle high-demand scenarios, the NCB-240/110H ensures instant and uninterrupted hot water, even with multiple fixtures or appliances operating simultaneously.
Easy Installation and Maintenance: The unit integrates seamlessly with existing plumbing and heating systems, offering straightforward installation. Built-in diagnostics and accessible service panels simplify maintenance, helping maintain long-term efficiency and reliability.
A Smart Choice for Modern Homes: For homeowners seeking a compact, energy-efficient, and reliable heating system, the Navien NCB-240/110H Combi Boiler offers outstanding comfort, reduced energy costs, and lasting performance, making it a wise long-term investment.
| Item | NCB-240/110H | |
|---|---|---|
| Dimensions | 43.9cm W x 74.4cm H x 32.5cm D (17.3" W x 29.3" H x 12.8" D) | |
| Boiler weight | 43.5 kg (96 lbs) | |
| Boiler Weight With Water | 46.3 kg (102 lbs) | |
| Installation location | Indoor wall-hung | |
| Venting type | Forced draft direct vent | |
| Ignition | Electronic ignition | |
| Natural gas supply pressure (from source) | 3.5 " WC to 10.5 " WC | |
| Propane gas supply pressure (from source) | 8 " WC to 13.5 " WC | |
| Natural gas manifold pressure (min-max) | -0.06 " WC to -0.24 " WC | |
| Propane gas manifold pressure (min-max) | -0.06 " WC to -0.26 " WC | |
| Connection sizes | Gas inlet | |
| Power Supply | Main supply | 120V AC, 60Hz |
| Maximum power consumption | Up to 15 amperes | |
| Materials | Casing | Cold-rolled carbon steel |
| Heat exchanger | stainless steel | |
| Venting | Exhaust | 2" or 3" PVC, CPVC, approved polypropylene 2" or 3" special gas vent type BH (Class III, A/B/C) 2" or 3" stainless steel |
| Intake | 2" or 3" PVC, CPVC, polypropylene 2" or 3" special gas vent type BH (Class III, A/B/C) 2" or 3" stainless steel | |
| Vent clearances | 0" to combustibles | |
| Safety Devices | Flame Rod, APS, Ignition operation detector, water temperature high limit switch, exhaust temperature high limit sensor, water pressure sensor, burner | |
| Temperature setting range | 30 - 60 °C (86 - 140 °F) | |
| Model | Heating | DHW |
|---|---|---|
| NCB-240/110H | 13,000 - 110,000 BTU/h | 13,000 - 199,900 BTU/h |
| Product | Labor | Parts | Heat Exchanger |
|---|---|---|---|
| NCB-H (Residential) | 1 Year | 5 Years | 10 Years |
| * The warranty periods apply only to single family, residential installations. | |||
A combi (combination) boiler is designed to heat a building, using hot water (similar to a boiler), but also includes the components and controls to internally heat the domestic hot water (DHW) required in the application. By having both heating and hot water in one unit, the combi will save space in the mechanical room and also save on the initial installation compared to separate appliances.
A combi (combination) boiler provides both space heating and on demand domestic hot water. In heating mode, water from the space heating system will flow through the heat exchanger and out to the system similar to a standard boiler. When a domestic hot water demand (open faucet) occurs, water flows through a separate heat exchanger in the combi, and a valve inside the unit diverts heating water over to the DHW heat exchanger. Space heating water is used to heat the domestic hot water until the demand ends. At the end of the domestic demand, the combi will switch back to supply space heating.
Inside the combi-boiler is a heat exchanger that separates the space heating flow from the domestic water flow, so the water in the heating system is isolated from the domestic hot water. The only thing that happens in the heat exchanger is that the heat from the higher temperature space heating water is transferred to the lower temperature domestic water.
Since the combi boiler provides both space heating and domestic hot water all in one unit, it can provide space savings over two or more units. Combi boilers also can provide endless hot water in DHW mode, similar to a tankless water heater. Combi boilers may also reduce the installation cost by reducing the number of appliances, possibly reducing the number of wall or roof penetrations required for exhaust and intake piping, and may reduce some of the gas piping requirements.
Combi-boilers do not require any additional requirements, compared to a condensing boiler and water heater. Compared to installing two different appliances, the installation may even have fewer requirements.
When a DHW (hot water) demand happens in a Navien combi boiler, the unit switches from space heating mode over to DHW mode. Referred to as DHW Priority, the unit will utilize the full capacity to heat the domestic hot water until the flow stops, providing endless hot water. While in DHW priority mode, the space heating is disabled. Even with a long shower or extended DHW run time, the home may lose a few degrees, but the chances of the home freezing during that time are extremely low.
The heating size of the boiler is determined by calculating the heat loss of the building, which is based on the size of the structure, the insulation value of the surfaces, and the door and window sizes. Since combi boilers also provide domestic hot water, the flow demand of the hot water fixtures also needs to be calculated to determine the maximum DHW flow required. A combi boiler size is chosen by ensuring that the unit can satisfy both demands. Typically with a combi boiler, the BTU input will be higher for the DHW demand than for the heating load. A qualified contractor can perform a heat loss and help recommend a proper boiler size.
