Spa air flow issues

[zamazing]

Did you have any luck with this? I have found a similar issue with mine. I had my pool replastered a couple of years ago, but up until recently, the jets worked fine. However, in the past few weeks I am finding that I do not get any bubbles. I have found that using a blower from a shop vac on the air inlet, while the spa is running for a couple of minutes fixes the issue temporarily - until I stop the pump again. When the pump stops, I hear water coming back up the tubes and can feel air coming back out of the air inlet. Is this normal?

I haven't been able to troubleshoot my spa any further. My PB is still taking a brute-force approach and plans to replace my air blowers with a higher-power commercial blower. Speaking of air blowers, have you considered adding one to your air inlet to solve your problem?

 

[zamazing]

An update.

I was able to convince my PB to meet with me to troubleshoot the spa before replacing the two blowers with a commercial blower as he had planned. We were able to determine that the spa had in fact been plumbed incorrectly! It turns out that the FILTER pump return was incorrectly plumbed into the AIR line and one of the two blowers was incorrectly plumbed into the WATER line. This is the reason the water pressure from the AUX SPA JET pump would pop the check valve and shut down that blower.

There is a way to tell if your pump is hooked up to the air side or the water side of your venturi valves. If the pump is correctly hooked up to the water side, then the water will flow like a fountain from the nozzle. On the other hand, if the pump is incorrectly hooked up to the air side of the venturi, the water will just spill out of the fixture with little pressure because it will be coming from the outside of the nozzle where the air is intended to be drawn.