13. Selection of control mode
System application
In systems with relatively small pressure losses in the distribution pipes.
•
Two-pipe heating systems with thermostatic valves
– dimensioned for natural circulation
– with small pressure losses in those parts of the system through which the total quantity of
water flows (for example boiler, heat exchanger and distribution pipe up to the first
branching)
or
– modified to a high differential temperature between flow pipe and return pipe (for example
district heating).
•
Underfloor heating systems with thermostatic valves.
•
One-pipe heating systems with thermostatic valves or pipe balancing valves.
•
Primary circuit pumps in systems with small pressure losses in the primary circuit.
In systems with a fixed system characteristic.
Examples:
•
one-pipe heating systems
•
boiler shunts
•
systems with three-way valves
•
domestic hot-water circulation.
If an external controller is installed, the pump is able to change from one constant curve to
another, depending on the value of the external signal.
The pump can also be set to operate according to the max. or min. curve, like an uncontrolled
pump:
•
The max. curve mode can be used in periods in which a maximum flow is required.
This operating mode is for instance suitable for systems with hot-water priority.
•
The min. curve mode can be used in periods in which a minimum flow is required.
In systems requiring a constant flow, independently of pressure drop.
Examples:
•
chillers for air-conditioning
•
heating surfaces
•
cooling surfaces.
In systems requiring a constant tank level, independently of the flow rate.
Examples:
•
process water tanks
•
boiler condensate tanks.
In systems with pumps operating in parallel.
The multi-pump function enables the control of pumps connected in parallel (two to four
pumps) without the use of external controllers. The pumps in a multi-pump system
communicate with each other via the wireless GENIair connection or the wired GENI
connection.
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Select this control mode
Constant differential pressure
H
Q
Constant temperature and constant
differential temperature
H
Q
Constant curve
H
Q
Constant flow rate
H
Q
Q
set
Constant level
H
Q
"Assist" menu
"Setup of multi-pump system"