Grundfos ALPHA2 User Manual

15
Changing from recommended to alternative pump setting
Heating systems are "slow" systems that cannot be set to the optimum
operation within minutes or hours.
If the recommended pump setting does not give the desired distribution of
heat in the rooms of the house, change the pump setting to the shown
alternative.
Explanation to pump settings in relation to performance curves,
see 11. Pump settings and pump performance.
7.2 Pump control
During operation, the pump head will be controlled according to the
principle "proportional-pressure control" (PP) or "constant-pressure
control" (CP).
In these control modes, the pump performance and consequently the
power consumption are adjusted according to the heat demand in the
system.
Proportional-pressure control
In this control mode, the differential pressure across the pump is
controlled according to the flow.
The proportional-pressure curves are indicated by PP1 and PP2 in the
Q/H diagrams. See 11. Pump settings and pump performance.
Constant-pressure control
In this control mode, a constant differential pressure across the pump is
maintained, irrespective of the flow.
The constant-pressure curves are indicated by CP1 and CP2 and are
the horizontal performance curves in the Q/H diagrams. See 11. Pump
settings and pump performance.

Grundfos ALPHA2 Specifications

General

Max Head	8 m
Voltage	230 V
Frequency	50/60 Hz
Type	Circulator Pump
Max. operating pressure	10 bar
Series	ALPHA2
Connection Type	Threaded
Protection Class	IP42
Liquid Temperature Range	2°C to 110°C
Energy Efficiency Index	≤ 0.23
Connection size	G 1 1/2
EEI	≤ 0.23