Display shows E19; heater may indicate condensate or blocked drain fault on condensing models.

Safety: Turn off power. Condensate is mildly acidic; wear gloves and eye protection.

Steps:

• Locate condensate trap: On condensing Lochinvar pool heaters, find the plastic condensate trap and drain line at the bottom of the heat exchanger.
• Inspect for blockage: Remove the trap (have a container ready for water) and flush it with clean water to remove debris or slime.
• Check drain line: Ensure the drain hose runs downhill with no kinks and terminates at an approved drain. Clear any obstructions.
• Float switch: If equipped, inspect the condensate float switch for free movement and intact wiring.

Reassemble, restore power, and test. If E19 persists, the float switch or wiring may need replacement.