42
Figure 67. Piping for Multiple Heaters, Primary/Secondary
EXTEND 12” PAST
HEATER INLET FOR
HYDRAULIC BALANCING.
4550
BRANCH MAIN BRANCH MAIN BRANCH MAIN
20 GPM 1-1/2" 1-1/2" 20 GPM 1-1/2" 1-1/2" 20 GPM 1-1/2" 2"
30 1-1/2" 1-1/2" 30 1-1/2" 2-1/2" 30 1-1/2" 3"
40 1-1/2" 2" 40 1-1/2" 3
*Sizing based on10 ft/sec flow rates
MINIMUM PIPE SIZES
2 UNITS 3-4 UNITS 5-6 UNITS
5550-8550
BRANCH MAIN BRANCH MAIN BRANCH MAIN
30 GPM
40
60
80
2"
2"
2"
2"
2"
3"
3"
4"
30 GPM
40
60
80
2"
2"
2"
2"
2-1/2"
3"
4"
4"
30 GPM
40
60
80
2"
2"
2"
2"
4"
4"
5"
5"
MINIMUM PIPE SIZES
2 UNITS 3-4 UNITS 5-6 UNITS
40 1-1/2" 4"