Grundfos ALPHA2 User Manual

25
12. Fault finding chart
Warning
Before starting any work on the pump, make sure that the electricity
supply has been switched off and that it cannot be accidentally
switched on.
Fault
Control
panel
Cause Remedy
1. The pump
does not run.
Light off. a) One fuse in the
installation is blown.
Replace the fuse.
b) The current-operated or
voltage-operated circuit
breaker has tripped out.
Cut in the circuit breaker.
c) The pump is defective. Replace the pump.
Shows "- -". a) Electricity supply failure.
Might be too low.
Check that the electricity supply
falls within the specified range.
b) The pump is blocked. Remove the impurities.
2. Noise in the
system.
Shows a
number.
a) Air in the system. Vent the system.
See 10.3 Venting of heating
systems.
b) The flow is too high. Reduce the suction head.
See 11. Pump settings and
pump performance.
3. Noise in the
pump.
Shows a
number.
a) Air in the pump. Let the pump run. It vents itself
over time.
See 10.2 Venting the pump.
b) The inlet pressure is too
low.
Increase the inlet pressure or
check the air volume in the
expansion tank, if installed.
4. Insufficient
heat.
Shows a
number.
a) The pump performance
is too low.
Increase the suction head.
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