HELIX VX-050 Installation, Operation & Maintenance Manual page 20

5 - HYDRONIC PIPING
5-8C Multiple Boilers Using Primary/Secondary Pumping with Open External Primary Loop
12"/305mm Maximum Separation
12"/305mm
Existing closely spaced tees
Maximum
in primary system loop
Separation
CH/System
Pump
System
Size common piping
Temperature
per maximum heat
Sensor
capacity of entire
system
Limit
length to
5' (1.6m)
Up to 16
boilers
20