About the Boiler 7
2.2 Parts of the Boiler
Front View
Coaxial
(Intake/Exhaust)
Bottom View
a
b
c
d
f
g
h
e
#
Description
a
Gas connection
b
Condensate water outlet
c
DHW hot water outlet connection
d
Space heating supply connection
e
Return adapter filter
f
Cold water inlet connection
g
Pump drain plug
h
Central heating return connection
2.1 Description of the Boiler
The Navien NCB700 boiler is available in 4 models:
NCB700-24L, NCB700-28L, NCB700-34L, NCB700-40L.
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.
●
Thermostat Control Failure: Should the thermostat fail to
function properly, the boiler’s gas supply will be shut off
automatically as a safeguard.
●
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. About the Boiler
