Navien NCB-20LHWE, Руководство по установке и эксплуатации

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Model
Gas type
G20 G31
[20 mbar] [37 mbar]
w o lf s a G w o lf s a G n o it p m u s n o C t u p t u O
Load Kcal/h kW kW m
3
/h m
3
/h
NCB-20LHWE
Max. 16,770 19.5 20.0 2.142 0.804
Min. 3,354 3.9 4.2 0.450 0.169
NCB-23LHWE
Max. 20,124 23.4 24.0 2.570 0.964
Min. 3,354 3.9 4.2 0.450 0.169
NCB-28LHWE
Max. 24,317 28.3 29.0 3.106 1.165
Min. 4,214 4.9 5.1 0.546 0.205
NCB-33LHWE
Max. 28,509 33.2 34.0 3.641 1.366
Min. 3,268 3.8 4.0 0.428 0.161
c. Fully open several hot water fixtures and set the boiler
to operate at 1-stage MIN mode.
Note
For operation mode selection, refer to “11.4
Setting the Operation Mode” on page 47.
Measure the CO
2
value at low fire.
If the CO
2
value is not within 0.5% of the value listed in
Table 2, the gas valve set screw will need to be adjusted.
If adjustment is necessary, locate the set screw as shown
in Figure 8. Using a 5 /
32
in or 4 mm Allen wrench, turn
the set screw no more than
1
/
4
turn clockwise to raise or
counterclockwise to lower the CO
2
value.
Figure 8. Set Screw Location
Note
The set screw is located behind the screw-on
cover. This must be removed first.
d. Fully open several hot water fixtures and set the boiler to
operate at C.MAX (20/23/28LHWE) or C.MAX2(33LHWE)
mode (refer to “11.4 Setting the Operation Mode” on
page 47). Measure the CO
2
value at high fire.
If the CO
2
values do not match Table 2 at high fire,
do not adjust the gas valve. Check for the proper Gas
Orifice.
DANGER
Improper gas valve settings can cause severe personal injury
or substantial property damage.
66 Appendices