In pool mode (at 2350rpm) and pool heating mode (at 2850rpm), everything runs fine. When I turn on my connected spa (3150rpms), it heats and works fine, and then I turn on the air blower (Silencer 1.5HP 220v), and that produces bubbles and works fine. Will run the spa for an hour or so, and then if I turn off the air blower, the GFCI 20 amp double pole circuit breakers for both my heater and my pool pump trip (so 2 breakers trip). I can reset the breakers, and everything seems fine again, until I repeat the sequence. If I run the spa and I turn off the spa first and leave the air blowers on, nothing trips until I turn off the air blower. What's strange though, is if I turn on the air blower alone, not in spa mode, and then turn the air blower off, nothing trips. So, by process of elimination, it seems that the air blower only trips the breakers when turning off in spa mode. Anyone might know the cause of this? Could it be a bad breaker? (I wouldn't think so cause it works fine otherwise), or could it be the heater and the air blower shutting off together that's overloading the circuits? FYI...this has happened before in the past but very infrequently. Now it's happening pretty consistently. And it's only when I turn off the air blower.... Thanks.