If your hot tub encounters circulation problems or displays error codes such as "dr" or "HH," it's likely due to a significant air pocket trapped within the plumbing, causing reduced water circulation, known as an "airlock." To resolve this issue, follow these steps:
1. Turn off the spa circuit breaker.
2. Open the cabinet panel attached to the pump/motor connected to the control pack via plumbing.
3. Locate the two pipes connected to the pump/motor secured by large unions/nuts. Slowly loosen the top union/nut to release air, then promptly retighten it as water begins to flow out, allowing excess air to escape from the system.
4. Turn the circuit breaker back on and activate the pumps/jets to ensure water flows out of the jets.
To minimize the likelihood of an airlock, fill the tub by placing the garden hose down the filter compartment to prevent air bubbles from forming within the system.
During the spa's self-priming process (indicated by "Pr" on the control panel), press the "Jets 1" button on and off to expel any air from the lines. Only perform this action a few times to avoid placing excessive pressure on the motor. Repeat the procedure if pump 2 is installed. Note that if the spa has a circulation pump, this method cannot be used, and air removal must be done using the above steps.
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