[Ian Sheppard]

Everybody else seems to run the flow controllers at around 50 , and i have to run mine at 85 and always have .
I assume that i have the same setup as a lot of people .....

Shurflo 100psi , 8000-441-138 , 3.78 lpm pump
100 m microbore going to gardiner red fans
Usual 3 button controller that all suppliers seem to sell .
At 85 flow i get about 1.7 lpm through the fans.

The only thing i can think is that some of you have the other shurflo that is a higher lpm rate .
Anybody shed any light please , what  do you guys run ?

In honesty the right flow setting is the one that suits each individual. Some will like a much higher flow for example if windows have lots of traffic film on them or tree sap for example.  Am older pump is likely to be less efficient due to wear on the pump head valves and the motor brushes. So this may mean that to achieve the same flow rate at the brush the older pump needs to run at a higher flow setting than a new one.  But we now get into the murky of flow dynamics and pressure dynamics. these blogs scratch the surface of those topics http://springltd.co/blog/49/pressure-dynamics-within-water-fed-pole-systems & http://springltd.co/blog/48/water-volume-delivered-to-glass