Since construction of my pool my filter pressure has been very consistent when the filter is clean, low-to-mid twenties, usually mid twenties. Historically it takes about three months to build to low thrities or more. And regardless of the how much pressure has increased the filters have been cleaned every three months since new. This last time was different though. I cleaned the filter *myself* vs having my pool service (that I've had since day 1) clean it. The pressure dropped to fifteen. So I have a couple of thoughts and questions.
First, is this an indication that the pool service tech doesn't clean it as well as I did? Thus the difference in post-cleaning pressure. That could make sense since he probably is only allowed to spend X amount of time at each customer and since it's mine I'm going to put more effort into it... thus cleaning better and reducing pressure more. I have never opening the system up after the service company cleaned to inspect how well they were cleaned so I have no basis for comparison to what they looked like after I cleaned them. However, when the service company cleans them they always take before and after pictures which they provide to me. There is always a drastic difference, not unlike when I cleaned myself this last time. Pictures aren't as telling as seeing in person though.
Second, obviously the pressure after my cleaning is low relative to history. Is the difference a sign of problem? Maybe this is great. No idea.
Overall I have been happy with the service company but am building confidence to drop them in lieu of the TFP methodology.
Thanks for your feedback.