Heater shuts off when the pump speed drops to low, even though water is still circulating.

Safety first: Turn off power before adjusting the pressure or flow switch.

• Review pump programming: Increase the pump’s low-speed RPM during heating cycles to meet Aquacomfort’s minimum flow requirements.
• Adjust pressure switch: Carefully adjust the water pressure switch per the service manual so it closes at the correct flow rate, not excessively high.
• Hydraulic check: Ensure that the heater is plumbed in a way that provides adequate pressure differential (e.g., not on a bypass that eliminates pressure drop).