Heat Siphon Short Cycling / Improper Control Logic

Unit short‑cycles: starts and stops frequently without reaching set temperature.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Oversized heater for pool volume, Faulty temperature sensor, Flow switch chatter due to marginal flow, Control board hysteresis settings

Safety first: Turn off power before adjusting wiring or sensors.

Check flow stability: Ensure the pump runs continuously while heating and that valves and filters provide steady flow. Correct any cavitation or air leaks.
Sensor check: Verify water temperature sensor accuracy and secure mounting.
Observe error codes: Watch the display during cycling for brief FLO, HP, or LP indications that may point to the root cause.
Professional tuning: A technician may adjust control parameters or recommend plumbing changes to reduce cycling.

Medium 3/5

Water Flow Switch

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