Navien LCB700-21RS Installation & Operation Manual page 24

Auto Air Vent
Pressure Gauge
S1
Temp.
Sensor
Circulating
High Limit Stat
TP
Heat
Exchanger
PS
Drain
Valve
Regular Boiler
<Regular Boiler Heating & DHW Cycle>
CAUTION
When installing an optional circulating pump, ensure that it
is installed in the proper direction. Also, install the circulator
pump to the return pipe and allow it to circulate hot water
towards the boiler. If a circulator pump is installed in the
wrong direction, the boiler's heat exchanger cannot be
vented properly, which may damage the boiler and cause
it to malfunction.
Auto Air Vent
Pressure Gauge
S1
Temp. Auto
Sensor Air Vent
High Limit Stat
TP
Circulating
Pump
Pressure Relief Valve
Heat
PS
Exchanger
Pressure
Sensor
EV
Expansion Vessel
Drain Valve
System Boiler
<System Boiler Heating & DHW Cycle>
Refer to "7. Setting the DIP Switches" to control the
Note
boiler using the external CH Controller and DHW Tank.
24 Installing the System Piping
<S Plan Layout> <Y Plan Layout>
Auto Air Vent
2Way 3Way
Valve Valve
Pressure
Relief
Valve
E
Pump
V
Expansion Automatic
Vessel Bypass
Valve
Temp.
Sensor
S3
DHW
Tank
Pressure
Sensor
Expansion
EV
Vessel
<S Plan Layout> <Y Plan Layout>
Auto Air Vent
2Way 3Way
Valve Valve
Automatic
Auto Air Vent
Bypass
Valve
Temp.
Sensor
S3
DHW
Tank
Expansion
EV
Vessel
Auto Air Temp. Pressure
Vent Sensor Gauge
S1
High Limit Stat
TP
Circulating Pump
Pressure
Relief
Valve
Heat
Pressure
Heat Storage
PS
Sensor
Exchanger
EV
Expansion Vessel
Drain Valve
Combi Boiler
<Combi boiler Heating & DHW Cycle>
When installing the system, follow these guidelines:
Use only pipes, fittings, valves, and other components (such as
solder), that are approved for use in potable water systems.
Tighten the connection valves with care to avoid damage.
The external hydraulic bypass valve is required.
An additional expansion vessel must be installed to the system
in the central heating return.
AAV
3Way
Valve
Automatic
Bypass Valve
Mixing Valve
AAV
Tank
Flow Flow
Valve Sensor
FV FS