Potterton PRIMA 30C User Manual page 8

TECHNICAL DATA - Page 8
Circulation Pump Selection
TABLE 2
The resistance through the heat exchangers when operating
with a water flow rate producing an 11°C temperature rise at
maximum boiler output is shown in TABLE 2. If other
controls, such as three-position valves are used in the
system, the resistance through them, quoted in their
manufacturers literature must be taken into account. The
pump may be fitted on either the flow or return and on
FULLY PUMPED systems MUST be wired directly to the
boiler terminal block, see Fig 14.It must be fitted with two
isolating valves which are positioned as close to the pump
as possible. Isolation of the valves must always leave the
open vent unobstructed.
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