For those of you using Pentair's IntelliPh automation to maintain your acid. I just replaced my pump head, again for the third year in a row due to corrosion and failure. More importantly, I want to let you know that I also found my injector had failed.
Apparently, from what I've "heard," the injector that came with the unit "may" have a faulty check valve. I discovered mine when I replaced my acid hose connection to the injector. The injector was allowing water to dispense when the injector hose was removed. My local pool store contacted Pentair and they shipped a new injector part #522513Z. I'm in the process of installing it. What I though would've been a simple straight-forward process has turned into a bit of nagging problem.
The new acid hose is quite difficult to install through the new compression fitting even using silicon lubricant. Took me a couple of tries using brute force and awkwardness. I've also encountered slow water leaks where the injector is jointed to the water line and itself. Have retaped and reinstalled twice and am now working on a third time. Never had the problem with the old injector.
Hopefully this posting will be of some help to those using this product.