Navien NHB Series, Installation & Operation Manual

Page: 20 / 135

20 Installing the System Piping
Oxygen Elimination
This boiler may only be installed in a pressurized closed-loop
heating system, free of air (oxygen) and other impurities. To avoid
the presence of oxygen, ensure all of the air is removed from
the system during commissioning via strategically placed and
adequately sized air removal devices, located throughout the
heating system.
Note
See the examples of system application at the end of
this section detailing the installation location of the air
removal device, in case an additional air removal device
is required for a specific application.
WARNING
Ɣ
Immediately repair any leaks in the system piping to avoid
adding make-up water. Make-up water adds oxygen and
minerals to the system that may lead to heat exchanger
failure.
Ɣ
Failure to follow these instructions may result in poor
performance, unnecessary wear of system components and
premature failure.
CAUTION
Do not solder piping directly onto the water connections,
as the heat may cause damage to internal components. Use
threaded water connections only.
3.1.2 Essential Elements in a Space Heating System
Boiler Piping Options
The following illustrations show various boiler piping options.
Pressure Relief
Valve
Auto Air Vent
Supply
Return
<Supply / Return Bottom>
Pressure Relief Valve
Air Vent Bushing
Double Nipple
Tee
Auto Air Vent
Supply
Return
<Supply Top / Return Bottom>