2. About the Boiler
2.1 Description of the Boiler
The Navien NCB-H boiler is available in 5 models:
NCB-190/060H, NCB-190/080H, NCB-240/110H,
NCB-240/130H and NCB-250/150H.
The main features are as follows:
Power Interruption: When the power is restored
●
after a power failure, the boiler will automatically
start and return to normal operation. A manual
reset is not required.
Freeze Protection: A sensor inside the boiler
●
automatically detects the temperature and,
if necessary, initiates a safety heating cycle to
prevent internal equipment damage due to
freezing temperatures.
Short-Circuit Protection: Any short-circuit
●
occurring in the boiler's electrical circuit
immediately blows the internal glass fuses and
automatically cuts off the gas supply.
Lightning Protection: Each boiler is specially
●
grounded, both internally and externally, to
protect against lightning strikes.
Carbon Monoxide Protection: The boiler is
●
designed to maintain a safe air-to-gas ratio and
combustion rate. This function is continuously
monitored by the boiler's air ratio control module.
Auto Fan Detection: The rotation of the fan is
●
automatically detected and controlled. Fan failure
will stop the operation of the boiler.
Boiling Prevention: Excessive temperatures will
●
automatically stop the boiler.
2.2 Parts of the Boiler
2.2.1 Front View
Combustion
Air Intake
2.2.2 Bottom View
A
B
C
2.7"
3.5"
3.3"
(68 mm)
(88 mm)
(85 mm)
17.3" (440 mm)
#
Description
A
Heating Supply
B
Domestic Hot
C
Gas Connection
D
Domestic Cold
E
Auto Feeder Inlet (Make-up Water)
F
Condensate Outlet
G
Heating Return
Exhaust
Gas Vent
D
E
F
G
2.7"
(69.5 mm)
2.9"
2.5"
(74 mm)
(63 mm)
9.6" (244 mm)
About the Boiler
7