"brought this pump as I had enough listening to old pump for two years churning away in cupboard and now all I hear is tinnitus. Have to say was not easy getting old one off as it was giving a good fight with pump pliers and gentle tapping with a squirt of WD40, resorted to buying new pliers and good quality which done the job no problem. Very good and like everyone else I'm sure, you will be back every day to confirm its still on. Would recommend without hesitation."
"Brought to replace a very old pump that had become very noisey. This one replaced it perfectly, very easy to fit, all seals required were included. It auto bleeds itself of air and is SO QUIET that I have to keep checking that it is working!! It also automatically varies its speed so it and the heating system should always be working in its most efficient way. To early to say about reliability but Grundfos stuff is normally very good."
"I bought this for my own house so I could have a play with it without having to let a customer watch me being very confused, and so learn while sorting out my heating which had the pump stuck on high speed. This was to replace an old, switched, 3 speed circulator.
I have previously spent time on the Grundfos Ecademy (sic.) training to try to understand these modern pumps and had glanced at the technical downloads available.
When I opened the packaging, I was dismayed to find instructions in incomprehensible pictograms. So I rang technical support (my internet was down, and I prefer paper format anyway) to be told that the 3 speeds are equivalent to the old three-speed pumps (fair enough) and the other 4 are 'all proportional' NOT constant pressure (flatly contradicting the technical info on the Grundfos website which states that 2 are constant pressure and 2 are proportional pressure) and that it is mostly 'a case of 'trial and error'. I got the impression the lady on the phone wasn't a very technical person, actually.
So, if a product, designed at great expense by engineers, is to be fitted by people with no help to understand how it works, it is a waste of money - may as well just fit a standard UPS model instead of the Alpha. That said, HAD technical support not decided to fob me off and sent me the proper manual instead of the pictograms, I'd probably like this. As it is, don't bother spending the extra.
The pump is self-venting. A disadvantage is the lack of bleed screw also means that if the shaft seizes, you have to dismantle as there is no way of inserting a screwdriver into the end of the shaft to rotate it.
The wired plug is good as it means you can position the pump as desired and then just connect the plug instead of having to either wire first and plumb around the wires, or plumb first and then hope you can still get into the terminal box.
The pump is reasonably quiet, but no quieter than my 16-years-old one. It uses less electricity, but this model does not show the power consumption in use like the AUTO model does.
In the event, I decided I could mend my old circulator - all was wrong was the speed selector was stuck on the wrong setting, so I took my new pump off again and re-instated the old one. Still stuck, but now it's on the right setting.
Thinking I'll set this Alpha up on a workbench and see how it behaves: it'll be a learning (pump) curve..."
"Our old pump failed & within a couple of hours I had purchased this off the shelf & fitted as a direct replacement for the old one - no pipework changes needed! Seems to be a top quality item & is so very, very quiet compared to the old one. Not sure how I can rate reliability after two days...ask me in a decade!"