"we have a modern boiler on an old system this pump should sort out our pressure problems with THV and the DHW taking a long time to heat up. can not put an accurate reliability star as only just fitted it, ask me again in 5 years."
"The Grundfos Alpha pump in my house was a few years old, when we moved in 7 years ago. It tripped out the mains RCD at 08.20am. I traced the fault, ordered a new Alpha2L pump from my local Screwfix and had it all replaced by lunchtime. The longest part of the job was getting the air out of the system. The pump was easy to install and set up. Looking forward to not touching it again for at least 10 years."
"Last pump only lasted 2.5 years before getting seized up. Could not get it to start and it has suddenly got very cold out. Needed emergency fix so took a risk and got this same make and size from Screwfix. Took 10-20 mins to fit, comes with rubber washers. Had to buy pump pliers but well worth it. Would help if the website shows dimensions. Overall seems excellent, very quiet pump which was worrying at first as I wasn't sure it was on until downstairs radiators started warming up. Works out much cheaper and faster than calling a professional at this time of year. (xmas/new year week)."
"Bought one of these for each of the houses we have had and have just fitted one to our new house. Works really well, and is getting all the rads hot what's really good it when just one or two rads needs heat they now run quietly.
"My old Grundfos CH pump had seized after 17 years of faultless service. The new Alpha 2 L was a straightforward replacement and the use of a plug at the pump end of the flex made it a lot easier to wire up than the old one. I'm using it in "proportional pressure" mode where it should adjust its speed to provide just the flow required, and it seems to be doing just fine; gets heat to all the rads at startup but when only one rad is on there is no excessive noise at the TRV or pump. As for reliability, I can only base this on the 17 years I got out of the old one.
The only negative is the instructions; all pictures, no words. Hopeless in understanding the modes of operation. I ended up downloading a much better guide from the Grundfos web site."
"The last pump we had was noisy and less flexible. Very easy to install and quiet. The pump has a number of options that help to vary the flow depending on the time of year. The product was expensive compared to others but the has proved to be very reliable."
"Suffered with noisy pump for 12 months replaced with a new one which the plumber fitted on a angle therefore same problem for another 12 months decided to purchase this one the silence is wonderful pump is running great a bit expensive down to the same old you get what you pay for??. Would recommend this product and service at Screwfix."
"Excellent bit of kit. Bought one of these to replace my existing pump on my oil fired boiler. I have been having lots of issues with the boiler overheating since I fitted a underfloor heating kit. Once installed, I set to constant pressure and its been great. All my boiler issues now resolved. Not the cheapest but worth ever penny!!"
"Very good pump from Grundfos to replace my old pump, Not cheap but worth it for the performance, Very quiet when running and all radiators get hot quicker than my old pump could manage even when it was new. I contacted Grundfos Technical before fitting as it is a new type smart pump that can increase and decrease depending on the demand and they said the pump was suitable for my system and suggested the setting to use, Only took 1 hr to fit from start to finish, Great Pump and good advice from Grundfos."
"My first one of these lasted till just outside of the warranty and then just stopped! Rotor was clear to run and motor and pump showed very little sign of wear. I conclude that the elaborate speed control system must be the reason. On a cold winters day what else could I do - I bought another one from Screwfix - Excellent price and in stock - LIFE SAVERS! Grundfos however unable to help with spares or repairs - what a waste to throw away a perfectly good pump just because a chip somewhere has failed. Maybe this pump is just too complicated? I am now on the lookout for a hot spare to keep on the self as I have little trust in the new one given that there was absolutely no warning before its predecessors failure."