Grundfos Alpha v UPS sorry cross post

[Nibber]

Hello, I have just had my 15year old Grundfos UPS 15 50 replaced with an Alpha 1 and the Alpha 1 seems quite a bit noisier than the the old one,
I have a new UPS3 sitting in a box and I am thinking of changing the Alpha 1 for the UPS3

if I understand it correctly, Alpha1 v UPS3
1. Alpha 1 is more energy efficient
2. Alpha 1 is noisier
3 Alpha 1 flow rate is much less

is this correct?
thanks

 

[John.g]

Does your version of the Alpha have the power displayed, watts, W?
Can you post a photo of the running pump with its LEDs displayed, this will show mode/setting.
How many rads?.

1&2 above, NO. 3. YES.,

 

[Nibber]

Does your version of the Alpha have the power displayed, watts, W?
Can you post a photo of the running pump with its LEDs displayed, this will show mode/setting.
How many rads?.

1&2 above, NO. 3. YES.,

thanks for the reply, Yes it does have Watts Displayed &16 Rads, picture attached, say flow rate 2.4m3/h UPS3 say 4 on the Grundfos site, constant III setting

 

[John.g]

thanks for the reply, Yes it does have Watts Displayed &16 Rads, picture attached, say flow rate 2.4m3/h UPS3 say 4 on the Grundfos site, constant III setting

That pump is pumping absolutely nothing at 4W, setting 1 in PP mode.
16 rads, you will require ~ 1 to 1.5m3/hr at say a 3.5M head to service those 16 rads.
Suggest, as a start, setting it to CP2 (second symbol on the right) and setting 2, you will require ~ 25 to 30W, see what this gives you, if < 20W try setting 3, (CP mode)

Have you a link to your pump?.

 

[Nibber]

That pump is pumping absolutely nothing at 4W, setting 1 in PP mode.
16 rads, you will require ~ 1 to 1.5m3/hr at say a 3.5M head to service those 16 rads.
Suggest, as a start, setting it to CP2 (second symbol on the right) and setting 2, you will require ~ 25 to 30W, see what this gives you, if < 20W try setting 3, (CP mode)

Have you a link to your pump?.

Sorry I think I haven't explained correctly, the picture is the brochure, my actual pump is running at 35watts in constant III mode

the brochure picture says flow rate is 2.4m3/h for alpha1 and according to Grundfos UPS3 says 4m3/h

 

[John.g]

Sorry I think I haven't explained correctly, the picture is the brochure, my actual pump is running at 35watts in constant III mode

the brochure picture says flow rate is 2.4m3/h for alpha1 and according to Grundfos UPS3 says 4m3/h

That's your pump curves below, I think.
Wht you have is three constant speed, CC settings, on the left, two PP modes first two symbols, on the right and two CP modes, last two symbols, on the right,

You are saying that you are running it on speed 3, III on the far left, is that correct??, if so at 35watts the pump is circulating ZERO, if you are saying the third LED on the right is illuminated then its running in CP1 mode and 35watts gives a flow of 1.6m3/hr, at a 3M head, is this it?.
To avoid any confusion can you just post a photo as requested.

 

[Nibber]

Here you go picture of actual pump, thanks

 

[John.g]

Here you go picture of actual pump, thanks

Certainly looks as if running in full speed mode so it cant be circulating anything at 35W, the boiler (if a heat only) should only run for a few seconds/minutes and the rads will/should be completely cold IMO, its possible that the pump is full of sludge and choked, just change it to CP2 (far right symbol) and if it runs at ~ 5W then pump sludged up or a valve shut somewhere.
Only other explanation is that its a 35watt pump and not 45/50 watt.

 

[Nibber]

Its a brand new pump and I am sure its working as it should, I'm just trying to understand the pros and cons of the Alpha1 and UPS3, thanks

 

[John.g]

The UPS3 is a far more powerful pump but won't consume any more power than the Alpha1 if running at the same head and flow. As its a bigger pump then it should run a bit quieter than the Alpha1 IMO
Cons, this model has a history of premature failures and disgracefully IMO, does not display the power.

If you don't mind, you might just change the Alpha1 mode briefly to CP2 and note the watts, then revert back, thanks.