The pump drew too much electrical current and triggered its fuse/overload protection. This can happen if the pump is working against a blockage or seized (mechanically stuck).
A clogged filter or closed valve in the chilled water circuit can make the pump work harder, leading to an overload trip.
The pump itself could be jammed or bearing failure caused it to seize, instantly overloading the motor.
Ensure that all valves in the chilled water loop are open and the water filter/strainer is clear. A blocked flow can strain the pump, so resolve this first if present.
If you have the training and it is safe to do so, switch off the chiller's main power and open the electrical control panel. Locate the pump motor overload switch or breaker (usually labeled for the user pump) and reset it. The overload may have a manual reset button that has popped out.
Close up the panel, turn the chiller power back on, and clear the alarm on the control interface. This often involves pressing and holding the alarm reset button for ~5 seconds until the alarm clears.
After resetting, observe the pump running. Check the pressure, flow indicators, or listen for any unusual noises from the pump. Ensure water is circulating normally through the system.
Repeat trips mean an underlying problem (electrical fault or a bad pump motor) still exists. A technician can test the pump motor and replace components like the motor starter or overload relay if needed.
