CleaverBrooks CBLE User Manual

750-91 (revised 2009)
Model CB-LE Packaged Boiler Manual
3-3
3.2 — Water Requirements: Hot Water Boiler
FIGURE 3-1. Maximum Circulating Rate Chart
3.2.2.1 — Multiple Boiler Installations
When multiple boilers are used, care must be taken to ensure adequate or proportional flow through the boilers.
Proportional flow can best be accomplished by use of balancing valves and gauges in the supply line from each
boiler. If balancing valves or orifice plates are used, a significant pressure drop (3 to 5 psi) must be taken across the
balancing device to accomplish the purpose.
If care is not taken to ensure adequate or proportional flow through the boilers, wide variations in firing rates
between the boilers can result.
In extreme cases, one boiler may be in the high-fire position while the other boiler or boilers may be at low-fire.
The net result would be that the common header water temperature to the system would not be up to the desired
point.
BOILER
SIZE
(BHP)
BOILER OUT-
PUT (1000)
BTU/HR
SYSTEM TEMPERATURE DROP - DEGREES °F
10 20 30 40 50 60 70 80 90 100
MAXIMUM CIRCULATING RATE - GPM
15 500 100 50 33 25 20 17 14 12 11 10
20 670 134 67 45 33 27 22 19 17 15 13
30 1,005 200 100 67 50 40 33 29 25 22 20
40 1,340 268 134 89 67 54 45 38 33 30 27
50 1,675 335 168 112 84 67 56 48 42 37 33
60 2,010 402 201 134 101 80 67 58 50 45 40
70 2,345 470 235 157 118 94 78 67 59 52 47
80 2,680 536 268 179 134 107 90 77 67 60 54
100 3,350 670 335 223 168 134 112 96 84 75 67
125 4,185 836 418 279 209 168 140 120 105 93 84
150 5,025 1,005 503 335 251 201 168 144 126 112 100
200 6,695 1,340 670 447 335 268 224 192 168 149 134
250 8,370 1,675 838 558 419 335 280 240 210 186 167
300 10,045 2,010 1,005 670 503 402 335 287 251 223 201
350 11,720 2,350 1,175 784 587 470 392 336 294 261 235
400 13,400 2,680 1,340 895 670 535 447 383 335 298 268
500 16,740 3,350 1,675 1,120 838 670 558 479 419 372 335
600 20,080 4,020 2,010 1,340 1,005 805 670 575 502 448 402
700 23,430 4,690 2,345 1,565 1,175 940 785 670 585 520 470
800 26,780 5,360 2,680 1,785 1,340 1,075 895 765 670 595 535

CleaverBrooks CBLE Specifications

General

Brand	CleaverBrooks
Model	CBLE
Category	Boiler
Language	English