The BH loan anemometer arrived today.  I could not help having a quick go round to see how things are.   Background, the MVHR was set up "by the seat of my pants" when we moved in 18 months ago.  By that I mean I just sent the inlet / exhaust vent restrictors wide open for those with long pipe runs, and closed them down somewhat for vents closer to the MVHR.  It's a radial system.   I downloaded the spreadsheet on the anemometer  loan thread and just input my values to that.