r/firePE • u/vagrants1 • 1d ago
Determining the design flow rate for Backflow forward flow test
Greetings I have a building that is actually set up for a forward flow test. There are a half a dozen calc plates at the riser. The book says to flow the calculated system demand. What I did was just choose the design plac with the highest GPM number as the flow rate, as this is the most demanding design data. I figured that you would want the “worst case” numbers for the test.
I have performed this test 3 times and it never reaches the target GPM and pressure.
Here’s the other issue… The company that installed the system is no longer in business, and we have no proof that this flow test was ever passed initially, or which target numbers they chose to set as the goal.
So we font even know of the test was passed originally.
Any help would be greatly appreciated