Display shows dr or DR; heater shuts off and spa may attempt several restarts; water does not heat properly.

Safety: Turn off power at the GFCI. Running the heater without proper water flow can permanently damage the heater tube.

• Step 1 – Check water level: Fill the spa to the recommended level (above all jets and skimmer openings). Top off if low.
• Step 2 – Remove and clean filters: Take out Vita Spa filter cartridges and rinse thoroughly. Try running the spa without filters to see if the dr code clears.
• Step 3 – Bleed air from heater: With power off, slightly loosen the heater unions to release trapped air until water flows steadily, then retighten. Restore power and monitor.
• Step 4 – Verify circulation pump operation: Ensure the circulation pump runs during heating cycles. If it is silent or only hums, it may be seized or air-locked. Try gently tapping the pump housing; if it still does not start, replace the pump.
• Step 5 – Inspect heater: If dr persists and the heater has been run dry, the internal thermal fuse may have opened. In that case, replace the Vita Spa heater assembly.