Nu-Way RGL 40, Installation & Maintenance Manual

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14
E
.0
4.
99
• G.
13.
11.
02
Start-up
Gas flow in operating state (V
B
)
Conversion factor (f)
Annual average air pressure
Key:
Q
n
= boiler rating [kW]
η
K
= efficiency [%]
H
i,n
= lower standard calorific value [kWh/m
3
]
f = conversion factor
B = barometric pressure [mbar]
p
G
= gas pressure at gas counter [mbar]
ϑ
G
= gas temperature at gas counter [°C]
Flow measurement
Determining flow duration at gas meter.
Calculated flow duration in seconds t
spec
for a flow volume of 200 litres (corresponding to 0.2 m
3
)
for the example given above is:
V
B
= 3,3 m
3
/h
Gas flow setting
Mean geodesic height of
supplied region ASL [m]
from 1 51 101 151 201 251 301 351 401 451 501 551 601 651 701
to 0 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750
Annual average of
air pressure
(mbar) 1016 1013 1007 1001 995 989 983 977 971 965 959 953 947 942 936 930
Measured flow duration in seconds [s] Measures
Greater than calculated flow duration t
spec
Increase gas flow
Less than calculated flow duration t
spec
Reduce gas flow
Equal to calculated flow duration t
spec
Gas flow achieved
V
B
V
n
f
------
3 1
m3
h
-------
,
0 94
,
-----------------
= 3 3
m
3
h
-------
,
= =
f
B P
G
+
1013
--------------
273
273
ϑ
G
+
--------------------
×
=
t
soll
0 2m
3
3600
s
h
---
× ,
V
B
m
3
h
------
--------------------------------------
720m
3
s
h
---
V
B
m
3
h
------
--------------------
720m
3
s
h
---
3 3
m
3
h
------
,
-------------------
218s = = = =