Biasi RIVA COMBI, Инструкция по установке и эксплуатации

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RIVA COMBI MANUAL - REV B 31
13.1 Circulator capacity as a function of flow rate:
Figura 13.1
The hydraulic specification in Fig 13.1 represents the pressure (available head for the
central heating system) as a function of the flow rate. The pressure loss due to the
internal piping in the boiler has already been subtracted.
When determining proper piping of the heating system, verify that the internal boiler circulator
will overcome the head loss of the system at the designed flow rate using the graph above. If
the internal circulator is
adequate , direct system piping can be utilized. See section 4 page 12
for suggested direct supply/return piping. If the internal circulator is inadequate , a secondary
circulator must be utilized. See sections 14 for suggested primary/secondary piping.
13.2 Expansion vessels:
The height difference between the C.h. PRV (24 on page 11) and the highest point in the system
may be 23 ft at most. For greater differences, increase the pre-load pressure in the C.h.
expansion vessel (21 on page 11) and the system when cold, by 0.1 bar for additional 3.3 ft. For
systems with volumes greater than 38.5 gallons (154l), an additional expansion vessel must be
provided.
The d.h.w. expansion vessel (25 on page 11) allows the expansion of the water inside the
storage tank (16 on page 11) and also absorbs the water hammer inside the pipe.
13. Circulator Sizing