M1 Callibration

[dcb568]

I am using the Neptune 1" flow monitor on my M1 return. According to the Neptune FFM, my M1 was running at 850 lph. My set up needs 3000 lph, so I recalibrated the M1 only to get it up to 1147 lph at max callibration! I guess I'm doing something wrong or the M1 has a flow memory needing to be cleared. Any ideas folk. Thanks.