Grundfos UPS2 pulsing.

[Toxic Ted]

Has anyone had feedback from Grundfos on this apparently common problem? A plumber i know fitted said pump and had problems with pulsing, but when he rang Grundfos to ask if there was a problem with them they denied all knowledge. I know this has been asked before, but just wanted to know if anyone had had a proper reply from Grundfos.

 

[Geyser]

Not come across it. Is it an air purging mode on start?

 

[ShaunCorbs]

yes its common on early one i find an no word from grundfos when i asked as they would have to replace the pump if the acknowledged it 😀

 

[Toxic Ted]

Not come across it. Is it an air purging mode on start?

If it is air purging then that makes it non compatible with systems that don't have flow sensors as the boiler will lock out.

 

[Damumbler]

I would check to see if the pump is on continuous mode.... See controlling the pump.

Look fit the following PDF online

Grundfosliterature-5173526.pdf

The pump setting can be changed with a single press on the push-button.
Figure 13 illustrates how UPS2 changes between the three speeds. This setting is indicated by a steady green light.

 

[Last Plumber]

Has anyone had feedback from Grundfos on this apparently common problem? A plumber i know fitted said pump and had problems with pulsing, but when he rang Grundfos to ask if there was a problem with them they denied all knowledge. I know this has been asked before, but just wanted to know if anyone had had a proper reply from Grundfos.

There was a component part that disliked voltage fluctuation or spikes caused by old equipment. You should be able to swap it at the merchant without any trouble if it s less than one year old

 

[CHRISX]

I would check to see if the pump is on continuous mode.... See controlling the pump.

Look fit the following PDF online

Grundfosliterature-5173526.pdf

The pump setting can be changed with a single press on the push-button.
Figure 13 illustrates how UPS2 changes between the three speeds. This setting is indicated by a steady green light.

Hello Damumbler and Toxic Ted,

I have recently fitted a Grundfos UPS2 to my Home`s Heating system.

IF You are asking about why the Speed indicator green light is `pulsing` - that is a specific `modulating` function setting which is turned On / Off by holding in the speed setting button for about 5 seconds.


You can set this `modulating` speed setting for any of the 3 speeds - basically what it is for is to modulate the speed down if a number of TRV`s close down or a Heating zone closes - although when on this setting it will still perform to the full extent of the Flow rate on the Pump curve graph.

I have this setting selected on my Home`s Heating systems Grundfos UPS2 Pump.


As Grunfos don`t seem to have told you this I may have misunderstood what You meant by the Pump is `pulsing` - if so I apologise.

Chris