HydroTherm HeaetNet V3 KN-10, Информация пользователя

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SETUP & OPERATION HeatNet Control V3 2.x
Page 15
added. The min fire rate is equal to the minimum BTUs that
can be delivered to the system.
Number of boilers * Turndown Ratio = Effective System
Turndown: 5 * 5:1 = 25:1.
Figure 5 Mixed Boiler System
System
MMBTU
Effective
Turndown
MOD
MAX
Priority 1
5:1
Priority 2
4:1
4.2 35:1 60% KN6, KN6
KN10, KN10,
KN10
3.8 42:1 70% KN4, KN4
KN10, KN10,
KN10
2.2 55:1 81% KN2, KN2
KN6, KN6,
KN6
3.6 90:1 72%
KN2, KN2,
KN2
KN10, KN10,
KN10
With the mixed boiler system, a lower minimum fire
rate/BTU can be delivered to the system by using small
boilers with larger boilers. This works in much the same
way as base loading.
Figure 6 KN Boiler Btu Chart (MBH)
KN2 KN4 KN6 KN10 KN20 KN30
Max Input 200M 400M 600M 1MM 2MM 3MM
Min Input
5:1
40M 80M 120M 200M 400M 600M
Mod Max
80%
160M 320M 480M 800M 1.6MM 2.4MM
Mod Max
70%
140M 280M 420M 700M 1.4MM 2.1MM
Mod Max
60%
120M 240M 360M 600M 1.2MM 1.8MM
Mod Max
50%
100M 200M 300M 500M 1MM 1.5MM
When selecting the Priority 1 boiler(s) for a high effective
system turndown, the BTU Min Input is selected first. (See:
KN Fusion & Boiler Btu Chart ). Next, the MOD-MAX
value of this Priority 1 boiler needs to be greater than : Mod
MAX % =
(Priority 1 „s Min Input + Priority 2 „s Min Input)
Max Input of the Priority 1 boiler
The reason for this is keep the continuity of BTUs linear
without a BTU bump (discontinuity) when boilers are added
or shed. This is illustrated in the
Boiler System Response 2
graph.
If redundancy is not required, the min inputs of the
Priority 1 boilers may be summed to lower the Mod Max %
value so smaller Priority 1 boilers can be used. The sum of
the min inputs would then need to be divided by the sum of
the Max Input of the Priority 1 boilers. The effect of this
would create a higher turndown. See:
EXCEPTION NOTES:
Mod MAX % =
( ((Priority 1 Min) * (#Priority 1‟s)) + Priority 2 Min)
Max Input of Priority 1 boiler * (#Priority 1‟s)
Example: (2) KN6s, (2) KN20s
Redundancy: (120 + 400)/600 = 87%
No Redundancy: (120 * 2) + 400)/(600*2) =54%