We were brought in to help with an existing pool/spa. The spa jets and air work independently when turned on individually. The jets and air work when turned on together if no jet bodies are in. When jet bodies are in, and we attempt to turn jets and air on together, the blowers idle up when the pump kicks on, and eventually overheat and the thermal sensor shuts them off. We’ve tried every type of jet body. We cut open the Hartford loops (above water level) and put air through the lines both ways. Homeowners say in the past everything worked perfectly. At one point, maybe two or three seasons ago, jet bodies were installed backwards by another company. They flipped them and the spa worked for another season. The following season the spa did not work upon opening and hasn’t worked since. If anyone has any thoughts or ideas I’m curious, because we are stumped. The boss has been doing this for 30+ years and says this is a strange anomaly and we’ve given away quite a bit of diagnostic time.