Display shows PR, PRR, or PRIMING at startup; pumps may run intermittently and heater is off.

Safety: Keep power on during priming but do not let pumps run dry for more than a few seconds.

• Step 1 – Open all jets: Turn all jet faces fully open to allow air to escape.
• Step 2 – Check valves: Ensure all slice valves near the pump and heater are fully open.
• Step 3 – Cycle pumps: Use the topside panel to turn pumps on and off in short bursts to help move air out of the lines.
• Step 4 – Bleed pump unions if needed: If pumps will not prime, turn off power and slightly loosen the pump discharge union until air escapes and water appears, then retighten.

Once water flow is established, the controller will exit priming mode automatically and normal heating will resume.