19
FIGURE 5-8B Multiple Boilers Using Primary/Secondary Pumping with Closed External Primary Loop
5 - HYDRONIC PIPING
Heating Load
Heating Load
Heating Load
Existing closely spaced tees
in primary system loop
12"/305mm
Maximum
Separation
Up to 16
boilers
CH/System
Pump
12"/305mm Maximum Separation
System
Temperature
Sensor
Size common piping
per maximum heat
capacity of entire
system
All internal
primary loop
ball valves
closed
Limit
length to
5' (1.6m)
3/8"/10mm Open
End Wrench may
be required to turn
valve
P/N# 240008852, Rev. M [07/2015]
