Other Products - Flex-Heat®
Hydronic Comfort System Boiler

When an application requires multiple boilers to provide sufficient capacity and some required redundancy, the Flex-Heat® Comfort System is an ideal choice! Utilizing Series GM™ gas-fired atmospheric boilers, the Flex-Heat system – with inputs of 456MBH to 3,990MBH and beyond (consult factory for larger requirements) – can meet a range of system requirements. The system uses less controls and piping than is used in other systems. The ability to use multiple boilers allows for maintenance of the individual boilers without shutting the entire system down, as would be necessary with a single boiler. In addition, firing multiple smaller boilers is much more efficient than the use of a single larger boiler, especially when only a portion of the capacity is required. The Flex-Heat System is an efficient, service-friendly and dependable system designed to provide years of superior performance.




Product Details:

Type: Semi-Commercial/Commercial
Construction: Cast Iron
Fuel: Gas-Fired (Natural or LP)
Input: 456 to 3,990 MBH
Output: 374 to 3,272 MBH
Venting: Natural Draft
Trim: Water
Ignition: Standing Pilot or Intermittent


System Number Module Quantity & Size Input (MBH) Gross Output (MBH) Gross Output (H.P.) Net Output (MBH) Combustion Efficiency
FH-456 2-5 456 374 11.2 325 82%
FH-513 1-5, 1-6 513 421 12.6 366 82%
FH-570 2-6 570 467 14.0 406 82%
FH-627 1-6, 1-7 627 514 15.4 447 82%
FH-684 2-7 684 561 16.8 488 82%
FH-741 1-7, 1-8 741 608 18.2 528 82%
FH-798 2-8 798 654 19.5 569 82%
FH-855 3-6 855 701 20.9 610 82%
FH-912 2-6, 1-7 912 748 22.3 650 82%
FH-969 1-6, 1-7 969 795 23.7 691 82%
FH-1026 3-7 1026 841 25.1 732 82%
FH-1140 1-7, 2-8 1140 935 27.9 813 82%
FH-1197 3-8 1197 982 29.3 854 82%
FH-1254 2-6, 2-7 1254 1028 30.7 894 82%
FH-1368 4-7 1368 1122 33.5 975 82%
FH-1482 2-7, 2-8 1482 1215 36.3 1057 82%
FH-1539 1-7, 3-8 1539 1262 37.7 1097 82%
FH-1596 4-8 1596 1309 39.1 1138 82%
FH-1710 5-7 1710 1402 41.9 1209 82%
FH-1824 3-7, 2-8 1824 1496 44.7 1301 82%
FH-1881 2-7, 3-8 1881 1542 46.1 1341 82%
FH-1938 1-7, 4-8 1938 1589 47.5 1382 82%
FH-1995 5-8 1995 1636 48.9 1423 82%
FH-2052 6-7 2052 1683 50.3 1463 82%
FH-2166 4-7, 2-8 2166 1776 53.1 1544 82%
FH-2280 2-7, 4-8 2280 1870 55.9 1626 82%
FH-2394 6-8 2394 1963 58.6 1707 82%
FH-2508 5-7, 2-8 2508 2057 61.4 1788 82%
FH-2622 3-7, 4-8 2622 2150 64.2 1870 82%
FH-2736 1-7, 6-8 2736 2244 67.0 1951 82%
FH-2793 7-8 2793 2290 68.4 1992 82%
FH-2850 6-7, 2-8 2850 2337 69.8 2032 82%
FH-2964 4-7, 4-8 2964 2430 72.6 2113 82%
FH-3021 3-7, 5-8 3021 2477 74.0 2154 82%
FH-3078 2-7, 6-8 3078 2524 75.4 2195 82%
FH-3192 8-8 3192 2617 78.2 2276 82%
FH-3306 5-7, 4-8 3306 2711 81.0 2357 82%
FH-3363 4-7, 5-8 3363 2758 82.4 2398 82%
FH-3420 3-7, 6-8 3420 2804 83.8 2439 82%
FH-3534 1-7, 8-8 3534 2898 86.6 2520 82%
FH-3591 9-8 3591 2945 88.0 2561 82%
FH-3648 6-7, 4-8 3648 2991 89.4 2601 82%
FH-3762 4-7, 6-8 3762 3085 92.2 2682 82%
FH-3876 2-7, 8-8 3876 3178 94.9 2764 82%
FH-3990 10-8 3990 3272 97.7 2845 82%




Series GM™ Boiler Dimensions

Boiler Model Number Jacket Depth
“A”
Jacket Width
“B”
Jacket Height
“C”
Left of Jkt. to C/L of Vent
“D”
Top of Jkt. to Vent Connector
“E”
Vent Size
“F” Dia.
USA, Nat. Gas Canada or LP
GM-05 25-3/4″ 19-1/4″ 35-1/4″ 9-3/4″ 29″ 7″ 8″
GM-06 25-3/4″ 22-3/4″ 35-1/4″ 11-1/2″ 30″ 8″ 9″
GM-07 25-3/4″ 26-1/4″ 35-1/4″ 13-1/4″ 31″ 9″ 10″
GM-08 25-3/4″ 29-3/4″ 35-1/4″ 15″ 31″ 9″ 10″