Harsco Industrial MACH C1500GG, Инструкция по установке и эксплуатации, Страница: 59 / 61

MACH® Gas-Fired Boiler
59
8.4 M
ACH
®
B
OILER
A
LTITUDE
D
ERATE
S
CHEDULE
For installations over 2000 ft elevations, a derate schedule is applied. The boiler input rating must be
reduced by 4% per 1000 ft.
This is illustrated using the following graph.
4% Derate Schedule
0
5
10
15
20
25
30
35
40
45
2000 3000 4000 5000 6000 7000 8000 9000 10000 11000
Altitude (ft)
T
o
ta
l
D
e
ra
te
(
%
)
Derate procedure is as follows:
With the boiler at high fire, adjust the gas valves (as described in section 3.10.4) to get 5% O
2
in the flue
gas. If this cannot be achieved, perform the following steps:
If the O
2
% is too high, then the inlet gas pressure should be adjusted to the minimum pressure
allowed, typically 5” w.c. The gas valve should be adjusted to obtain approximately 5% O
2
. If the
O
2
% is still too high, the fan speed may be lowered. This procedure should only be performed by
factory trained personnel.
If the O
2
% is too low, then the gas valve settings should be reduced.
This procedure is also described in Bulletin 06-08.