Condensing Combi-Boiler

The first high efficiency tankless condensing combi-boiler that can do it all

Navien NCB-E is the first high efficiency condensing combination boiler with the capacity to supply both heat and domestic hot water for larger homes — enough hydronic heat for a whole house, plus hot water to run two showers and a dishwasher all at the same time.

The Navien NCB-E saves installation time and reduces call backs. In addition, the NCB-E takes up 80% less space than a traditional floor standing boiler and tank water heater. Your customer now has more room, saves energy and enjoys all the hot water they need, whenever they want it.

Compare these advantages to anycondensing combi system

Dual Input
Dual inputs of up to 120k BTU/H for heating and 199k BTU/H for DHW
Supplies all the heat and domestic hot water that most houses require.
PVC Venting
PVC Venting
Low exhaust gas temperatures allows use of PVC, CPVC, ULC S636 and polypropylene vent systems, reducing installation time and costs. System can use 2" venting for up to 60', or up to 150' with 3" venting.
4.5 GPM@77° temperature rise for domestic hot water
Separate stainless steel flat plate heat exchanger for DHW creates the highest flow rate for any combi boiler in the industry.
Low Gas Pressure
Low gas pressure operation
Our negative pressure gas valve ensures maximum performance all the way down to a minimum gas pressure of 3.5" of water column.
Turn down ratio of 6:1 for heating and 11:1 for DHW
The sophisticated gas flow control system provides a high turn down ratio, reducing energy waste and excessive boiler cycling and enhances temperature control for DHW.
Gas Pipes
Uses existing ½" gas piping
Save time and effort in retrofit applications with ½" gas lines for up to 24'.
Dual Heat Exchange
Dual stainless steel heat exchangers
Resist corrosion better than copper to provide longer life.
Space saving design
Occupies 80% less space than a traditional floor standing boiler and storage tank.
Field Gas
Field gas convertibility
Dual venturi system allows for easy field convertibility from NG to LP operation. Orifice for LP conversion included.
For extraordinarily largedomestic hot water flow demand, the NCB-E can be cascaded with our NPE units.

NCB-E Applications

  • Air handler
  • Hydronic heating
  • Hydronic fan coil
  • Baseboard radiator
  • Radiant floor

Manifold Kits

For fast installation and maximum efficiency, install our system matched manifold kits.

NCB Series Primary Manifold KitGFFM-MCOZUS-001
Secondary Manifold KitGFFM-SKTZUS-001

NCB Models

Max Input: 120,000 BTU/H
Indoor or outdoor wall-hung
Max Input: 150,000 BTU/H
Indoor or outdoor wall-hung
Max Input: 180,000 BTU/H
Indoor or outdoor wall-hung
Max Input: 199,900 BTU/H
Indoor or outdoor wall-hung
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