Display shows dr or DR and heater shuts down; spa may attempt to restart.

Safety first: Turn off power at the GFCI breaker. A dry-fired heater can be dangerous and may be permanently damaged.

• 1. Verify water level: Fill the spa to the proper level, above all suction fittings and skimmer openings.
• 2. Open all valves: Ensure all slice valves near the pump and heater are fully open. Partially closed valves can starve the heater of water.
• 3. Bleed air from heater and pump: Loosen the unions on the heater and circulation pump until air and water escape, then retighten. This helps fill the heater tube completely with water.
• 4. Clean filters: Remove and rinse PDC Spas filters. Test briefly with filters removed to see if the dr code clears, indicating a flow restriction.
• 5. Reset the spa: After correcting water level and bleeding air, turn power ON and monitor the spa as it attempts to heat. If dr returns, shut power OFF immediately.

Call a technician if: dr persists after confirming proper water level, open valves, and good flow. The heater element may have been damaged by dry-fire and could require replacement along with inspection of the control pack.