Procedure To Refer Burner Operating Condition At An Altitude And/Or At A Combustion Supporter Air Temperature Different To The Standard Values (328 Ft Above Sea Level, 68 °F); Minimum Furnace Dimensions - Riello RLS 300/EV FGR Installation, Use And Maintenance Instructions

3.8.1 Procedure to refer burner operating condition
at an altitude and/or at a combustion supporter
air temperature different to the standard values
(328 ft above sea level, 68 °F)
Altitude Altitude bar. press.
ft a.s.l. m a.s.l. "w.c.
0 0 399
328 100 394
1.000 305 385
2.000 610 371
3.000 915 358
4.000 1.220 345
5.000 1.525 332
6.000 1.830 320
7.000 2.135 307
8.000 2.440 294
F - correction factor of discharge head and delivery in relation to temperature and altitude.
Reference conditions:
–
Air temperature 68 °F (20 °C)
– Barometric pressure 394 ''w.c. (1000 mbar)
– Altitude 328 ft a.s.l. (100 m a.s.l.)
3.9

Minimum furnace dimensions

The firing rates were set in relation to certified test boilers.
Fig. 6 indicates the diameter and length of the test combustion
chamber.
29.6
23.0
16.5
13.2
9.9
6.6
3.3
1.6
MBtu/hr
20102963
Technical description of the burner
bar. press. 0
mbar 32
1013,00 1,087
1000,00 1,073
977,40 1,049
942,80 1,012
908,20 0,975
875,80 0,940
843,50 0,905
811,85 0,871
779,80 0,837
747,80 0,803
1 5 . 7 1 9 . 7
2 3 . 6
760 1.5 1000
AIR TEMPERATURE
5 10 15
41 50 59
1,068 1,049 1,031
1,054 1,035 1,017
1,030 1,012 0,994
0,994 0,976 0,959
0,957 0,940 0,924
0,923 0,907 0,891
0,889 0,873 0,858
0,856 0,841 0,826
0,822 0,807 0,793
0,788 0,774 0,761
Example
Using the Tab. F , for an altitude of 3,000 ft and an air temperature
of 68 °F, an F factor value is obtained equal to 0.908;
if the capacity at the boiler furnace is Qfoc = 4,500 Mbtu/h, the cor-
rect output will be equal to:
Qburner = Qfoc / F = 4,500 / 0.908 = 4,956 Mbtu/h
Example RLS 500/EV FGR:
Output 18500 MBtu/hr: diameter 39.4 inch - length 16.5 ft.
Diameter (inches)
3 1 . 5 3 9 . 4 4 7 . 2
7.5
11.3 18.9 22.7
37870
14 GB
20 25 30
68 77 86
1,013 0,996 0,980
1,000 0,983 0,967
0,977 0,961 0,945
0,943 0,927 0,912
0,908 0,893 0,878
0,876 0,861 0,847
0,844 0,829 0,816
0,812 0,798 0,785
0,780 0,767 0,754
0,748 0,735 0,723
i nc hes
D9396
f t
MBtu
ft= 0,12
hr
40 °C
104 °F
0,948
0,936
0,915
0,883
0,850
0,820
0,790
0,760
0,730
0,700
Tab. F
Fig. 6