Circulation pump is not running; water surface is still and heater will not operate

Safety first: Turn off power at the GFCI breaker before working on the pump or plumbing.

The circulation pump must run for heating and filtration.

• Listen for operation: With power on, place your hand on the circ pump. If it is silent and not vibrating, it may not be receiving power or is failed.
• Bleed air: Turn power off, loosen the circ pump union until water flows, then retighten to remove air locks.
• Check for blockages: Inspect the suction side plumbing and any small inline filters or strainers for debris.
• Test voltage (if qualified): With power on and a call for heat, measure voltage at the circ pump terminals. If correct voltage is present and the pump does not run, replace the pump.

If no voltage is present at the pump when it should be running, the control board output or relay may be faulty and needs professional service.