Grundfos Alpha 1 15-50/60 new pump issues

[Neilk63]

Hi looking for some advice just had a Alpha2 Auto Adapt replaced as developed an issue direct from Grundfos they sent me the latest Alpha 1 15-50/60 130 in its place ...i fitted it myself after turning the head so that the flow arrow matched my existing pump .Issue is its supposed to be whisper quiet yet its making a loud humming noise when set on 3 running around 28W if I turn it down to 2 it is slightly quieter and just about manages to heat the system...i have a 1 year old Worcester greenstar 24i boiler new port valves and all rads (9;single 4 doubles) had powerflush then i had 5 new rads... after the powerflush Ibhave balanced the rads and all heat up as they should the F&E tank in my loft had a drain down and was cleaned and fresh inhibitor added...my boiler is due its 1st service tomorrow having spoken to Grundfos they feel my pump may need to be upgraded as it may not be suitable for the rads i have hence the humming noise ... ive a convential new system boiler downstairs kitchen Hot water tank pump and port valves in upstairs airing cupboard ...F&E in loft above ...just cant understand why the pumps noisy...i know i put the pump on correctly as i had to turn it so the flow arrow matched the one I took off which points down towards the boiler or it a case that the system needs a bigger pump Grundfos have asked me to ask the engineer
What is the required flow rate? (required from the pump to satisfy the system)

What is the required head/pressure? (required from the pump) Any help appreciated

 

[CBW]

A photo of pump position and arrow indicator might be best?

 

[Neilk63]

Please see pics arrow pointing down

 

[CBW]

Thanks, so it appears it could be the correct orientation. However those pump iso valves don’t look fully open, which would cause frictional resistance noise.

 

[Neilk63]

Hi cheers for the speedy response they are fully open now both sides where only a half turn off full open ...when the pump is on 3 though theres still a humming noise all rads heating up quickly though this morning

 

[Neilk63]

Oh and the pumps only pushing 26w on full which on info says 34w

 

[D_Hailsham]

i have a 1 year old Worcester greenstar 24i boiler

The i version is a system boiler, which has the pump built-in. Do you mean the Ri version, which uses a separate pump?

How many radiators do you now have?

I doubt very much if your "engineer" will be able to provide you with meaningful answers to Grundfos's questions.

 

[Neilk63]

Hi sorry the Worcester is the greenstar ri with pump located in upstairs loft

I have 13 rads 4 of em are doubles...

I installed it as the old grundfos i took out with the flow pointing downwards on the vertical pipes
It heats the system on 3 but really hums definitely not a whisper operation ...

 

[Neilk63]

Just read this on their website saying the flow arrow should be pointing upwards ...cant understand that the original grundfos was pointing down so i turned the new one to match

 

[D_Hailsham]

ive a convential new system boiler downstairs ... i know i put the pump on correctly as i had to turn it so the flow arrow matched the one I took off which points down towards the boiler

Just read that you have a system boiler. So you shouldn't need a second pump. Who said you did?

If the arrow is pointing towards the boiler it is either on the return (right-hand pipe at boiler) or it's pointing the wrong way!

Was the Alpha 2 installed at the same tiime as the boiler?

Which boiler did you have previously (make, model etc)?

 

[ianmcd]

.i fitted it myself after turning the head so that the flow arrow matched my existing pump

Turning the head does not alter the flow direction in any way, the pump body denotes the flow direction, your pump is upside down

 

[Neilk63]

They were saying a bigger pump not a second one the one they sent is only 10 days old ...

The system i had before
Was a Gloworm 80 ultima located downstairs
Upstairs airing cupboard a grunfos alpha 2 auto adapt pump ..hot water cylinder and 2 port valves
In loft f&e tank next to cold water tank

Alpha 2 failed after about 10 months of new boiler in it had been in a while on old system tho.

Ive had a powerflush done a month ago and F&E tank cleaned and inhibitor put back in..

So are you saying the flow should be pointing up not down

I did a straight swop when i put the new one in making sure the flow arrow faced the same way as the original sempt to work quietly for a few days but now its humming load ...all rads heat up and are balanced

 

[Neilk63]

Turning the head does not alter the flow direction in any way, the pump body denotes the flow direction, your pump is upside down

 

[Neilk63]

So when it came in the box it was pointing upwards

I took out the 4 bolts on the face and turned it so it matched the one that was on then rebolted the face .... so the flow arrow is going down ...totaly confused now ...everybody told me the flow arrow had to go the same way

 

[ianmcd]

They were saying a bigger pump not a second one the one they sent is only 10 days old ...

The system i had before
Was a Gloworm 80 ultima located downstairs
Upstairs airing cupboard a grunfos alpha 2 auto adapt pump ..hot water cylinder and 2 port valves
In loft f&e tank next to cold water tank

Alpha 2 failed after about 10 months of new boiler in it had been in a while on old system tho.

Ive had a powerflush done a month ago and F&E tank cleaned and inhibitor put back in..

So are you saying the flow should be pointing up not down

I did a straight swop when i put the new one in making sure the flow arrow faced the same way as the original sempt to work quietly for a few days but now its humming load ...all rads heat up and are balanced

No flow should be pumping down