I switched the Range Ring, but forgot to change the Range setting on my gauge. I recorded the Flow and left the site – do I have to re-test? Thankfully, NO, there’s an easy fix.
Just use the flow chart for your fan to locate the correct results!
Let’s say you read 33 CFM with your gauge set to Mid. But, yikes, later you remembered your DucTester actually had the Low Range Ring attached. You recorded 33 CFM.
Find the 33 CFM you recorded under the “Mid“ Range column on the flow table. Then, just move over to the correct 7.1 CFM reading under the desired “Low” Range. That’s it!
For the full article including the flow charts have a look at our blog:
That's a good solution for correcting the error after leaving the site.
I recommend changing the order of your range correction procedure. When your gauge calls for the next smaller ring, change the gauge setting first, then install the ring. You'll be less likely to forget to change the range setting if it's the first step and not the last step.
That's a great suggestion Dale.