Why does the RCD trip immediately upon power up?

• If this is a new installation, make sure that the RCD is wired correctly.
• Disconnect all the components (i.e., pumps, blower, ozonator, heater) and plug them back in one at a time to verify which component is causing the RCD to trip.
• Check for any loose connections or cut wires in the box.
• Plug in a new transformer

This is NOT intended as a service guide or a means for you,
as the consumer, to service your equipment in any way. this information is being provided for informational purposes only. Any and all service should be performed by a licensed spa technician.