Supply water volume = the volume from the generator outlet, through
the expansion vessel, pumps, supply
distribution system and heat exchange
Return water volume = the volume from the heat exchanger outlet,
through the return distribution system to the
Expansion Vessel Volume for Gas Pressurized Systems.
VT = V1 + V2 + V3
VT = Total expansion vessel volume
V2 = Volume required for expansion and contraction
V3 = Volume required for sludge space, pump suction coverage,
and reserve capacity
Volume Required for Pressurization
(Pmin)( ma )
Minimum gas pressure (should be above saturation
Maximum gas volume (Vmax = V2 + V3)
Maximum gas pressure (should be below pressure ratings of
piping, valves, and fittings)
Volume required for expansion and contraction
Volume of sludge space based on 6 inches of depth plus
the greater of the following two volumes. The volume
based on sufficient water to cover the top of the pump
intake line in the expansion vessel by 6 inches or the
volume needed for a 30-second supply of water based on
combined pump capacity.
These two equations
Volume Required for Expansion and Contraction.
show the development of this volume calculation.