Grundfos pump speed settings

[8-P]

We had a new boiler installed last week(Worcester) fwiw).

While up in the loft today I noticed they’ve changed the Grundfos UPS2 pump speed. Previously it was on proportional 3 and they have moved it to fixed 3(or powering it off has defaulted it back to this default setting).

How do I know what the best setting is? When we had the pump fitted probably 5 years ago it was noticeably noisier on fixed 3 but I’m more interested in performance/ efficiency.

Thanks

[B'stard Child]

8-P said:

We had a new boiler installed last week(Worcester) fwiw).

While up in the loft today I noticed they ve changed the Grundfos UPS2 pump speed. Previously it was on proportional 3 and they have moved it to fixed 3(or powering it off has defaulted it back to this default setting).

How do I know what the best setting is? When we had the pump fitted probably 5 years ago it was noticeably noisier on fixed 3 but I m more interested in performance/ efficiency.

Thanks

Do you heat 24/7

or

To a timed schedule with TRV's intervening?

[8-P]

Schedule with trv

[B'stard Child]

8-P said:

Schedule with trv

Then you don't want to be on a constant curve setting or as TRV's shut down the system is going to get very noisy and if you have a bypass valve set at a sensible level it's going to return a lot of water to the boiler

Can't find the really good article I read on pump settings but this one covers it

https://www.buildingservicestutor.com/hydronic-bal...

[8-P]

B'stard Child said:

Then you don't want to be on a constant curve setting or as TRV's shut down the system is going to get very noisy and if you have a bypass valve set at a sensible level it's going to return a lot of water to the boiler

Can't find the really good article I read on pump settings but this one covers it

https://www.buildingservicestutor.com/hydronic-bal...

Thanks

They are coming back next week to do a few things, something about it being cleaned out at the moment and then adding inhibitor. Perhaps they will change the setting at this point, if not I will do it myself although annoyingly I’m not going to be around.