Interesting ....... I have not had alarm but I have noticed a significant increase in bubbles in the lines when I do snap and tap; and at end of treatment when I take a syringe down that has been filled since we started ( to do rinseback) .. there are lots of tiny bubbles in it that I have never noticed before. I can get them to go to top with some tapping. But there are more of them ?
A trick I use is to close the red clamp for about 30 seconds after prime completes but before snap&tap. Cavitation creates large bubbles in the red line. When I open the red clamp, these bubbles go "whoosh" and sweep most of the tiny bubbles with them.
Doesn't really matter - I close the small one.If you do this, you need to wait a couple of minutes so the bubbles that go with the "whoose" make it all the way through the system. I typically prime, then have diner, the pick up at snap & tap later in the night.
If you're getting a lot of red 11's at the beginning of rinseback you might try to refill the 10cc syringe first. That would clear any bubbles in the short saline line (and syringe) that may have accumulated. Also like Simon Dog's closing the red clamp idea. I'll try that.