Selection Of Control Mode - Grundfos TPE 1000 Series Installation And Operating Instructions Manual

14. Selection of control mode

System application
In systems with relatively large pressure losses in the distribution pipes and in
air-conditioning and cooling systems.
• Two-pipe heating systems with thermostatic valves and the following:
- very long distribution pipes
- strongly throttled balancing valves
- differential-pressure regulators
- large 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.
• Primary circuit pumps in systems with large pressure losses in the
primary circuit.
• Air-conditioning systems with the following:
- heat exchangers, fan coils
- cooling ceilings
- cooling surfaces.
In systems with relatively small pressure losses in the distribution pipes.
• Two-pipe heating systems with thermostatic valves and the following:
- sized for natural circulation
- 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.
You can also set the pump to operate according to the maximum or minimum
curve, like an uncontrolled pump:
• Use the maximum-curve mode in periods in which a maximum flow is
required. This operating mode is for instance suitable for systems with
hot-water priority.
• Use the minimum-curve mode in periods in which a minimum flow is
required.
Select this control mode
Proportional pressure
H
H
set
H set
2
Q
Constant differential pressure
H
Q
Constant temperature and
constant differential
temperature
H
Q
Constant curve
H
Q
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