Navien NHB-055, Service Manual

Page: 21 / 147

NHB Service Manual 21 Version 1.0
Set of Front Panel DIP Switch 2 (2 switch unit)
The DIP SW 2 on the front panel configures settings for the type of
gas.
Before changing the settings, lift the rubber cover to access the
front panel DIP switches.
2
ON
NG LP
2
ON
1 2 3 4 5 6 7 8 9 10 1 2
ON ON
Switch Function Setting
2 Gas Type
Natural Gas 2-OFF
Propane Gas 2-ON
NOTE
●
As for altimeter setting and fuel setting, reads and checks
DIP SW only at the time of initial power application and
clearance of DIP SW set errors and after the completion of
checking, even if DIP SW is changed, does not apply the
change of setting.
●
If Main-Panel communication is not made for more than 10
seconds at the point of judging DIP SW setting, it operates
judging as Default value, Sea Level (0~ 2,000ft), NG. Then, if
communication normally operates, panel’s DIP SW setting
is not applied.
●
In order to change DIP SW setting, be sure to apply the
power of controller in the state that normal communication
with panel is possible.
4.2 Measuring the Inlet Gas Pressure
WARNING
The boiler cannot function properly without sufficient inlet
gas pressure. Measuring the inlet gas pressure should be
performed by a licensed professional only.
●
The inlet gas pressure must be maintained between 3.5 in and
10.5 in WC for natural gas and between 8.0 in and 13.5 in WC for
liquefied propane.
●
The appliance and its individual shutoff valve must be
disconnected from the gas supply piping system during any
pressure testing of that system at test pressures in excess of
1 /
2
psi (3.5 kPa).
●
The appliance must be isolated from the gas supply piping
system by closing its individual manual shutoff valve during
any pressure testing of the gas supply piping system at test
pressures equal to or less than
1
/
2
psi (3.5 kPa).
To measure the inlet gas pressure:
1. Shut off the manual gas valve on the gas supply line.
Gas Valve
Opened Closed