Circulation pump bore diameter

[oxgman]

Can anyone tell me what impact running a circulation pump with a larger diameter bore would have?
Currently running an old grundfos 15-6 on 22mm with 1 1/2 threads but looking at a lowara ecocirc 25-6.

 

[Last Plumber]

Why are you looking at installing that in place of the existing?

 

[oxgman]

Why are you looking at installing that in place of the existing?

The original pump is failing and newer pumps are more efficient. I run Lowara ecocirc pumps on four floors for ufh which work great.
I have read that the newer UPS3 and Alphas may have reliability issues.

 

[ShaunCorbs]

more flow through the pump

 

[Last Plumber]

There would be a higher flow rate/volume of water provided so long as the pipework and emitters are capable of carrying it.
If they are not, it would be pointless. There are a few things to take into account and a few situations to avoid with pump sizing and experience helps a lot. You might be better off asking a Plumber before you buy a pump that could create problems.

 

[Timmy D]

Bear in mind, that with pumps, bigger than required, is seldom better. Typically worse.

 

[king of pipes]

As above don't oversize your new pump it can throw off the balance of your system, providing your new pump can match the LPM curve of your old pump + a little through its settings then I don't see a problem . Kop