I have a Vokera Excel 80sp and it's making a loud low humming noise when it's used for heating and hot water.Is this likely to be the pump,or could it be the fan?Also, if it's the pump, I understand it's a Complete UPS 15-50 pump.I've seen the Grundfos UPS 15-50 pump available.Is this the same type of pump that I can use?

Mauro Nocivelli, August 2006

Just to help anyone that's searching and has found this thread: The excell 80 SP Fan can be noisy. And yes, the Grundfos pump can be used.

Alan, May 2008

did you get this resolved? mine makes the same noise and i've never been able to prevent it!

marc, October 2006