Ross Mackay Forum Moderator 94 Posts
Re: Why does our new pump have a lower flow rate?6 April 2011 at 1:29pm
Your new 2 pole speed pump obviously has a much steeper curve than the older 4 pole speed pump.
Your new piping on the discharge is causing more friction losses in a system that has significant friction losses already.
This would result in a higher head and lower flow. I suggest you fit a 2 x 3 increaser on the discharge of the new pump and refit all the rest to the existing 3-inch line.