Grundfos Alpha pump electrical load

[Peter Lee]

The pump in my system is behaving strangely. Normally it indicates that it is running at about 43W. Since Xmas morning, it has only been at about 18W. When it starts up, it goes up to 45 for a few seconds and then back down 3 or 4 times. Added to this, it worked perfectly for a time yesterday. Really confusing and frustrating. Just realised it's actually an Alpha 2

 

[Deleted member 267285]

I don’t know enough about these to answer, but maybe post or ask it to Ben moved to plumbing and heating forum? Also taken this from Grundfos website:

The reduction in power consumption has been achieved by using the latest permanent magnet motor technology and this power consumption can be as low as 5 watts. The variable speed modulating modes allows the pump to match its performance to the system requirements, helping to reduce noise when thermostatic valves are closing down.