Light Rail Manila Corp. (LRMC) announced Thursday it is tightening maintenance protocols after a defective air-conditioning valve caused a water leak inside a 4th-generation Light Rail Transit Line 1 (LRT-1) train set.

The incident gained public attention after a commuter posted a video on social media Wednesday showing water leaking from the ceiling onto passengers traveling between Ninoy Aquino and Fernando Poe Jr. stations.

LRMC said its maintenance team monitored the affected light rail vehicle and deployed a technician to inspect the problem.

Following the technician’s recommendation, the train was promptly pulled from the revenue line and brought to the depot for a comprehensive assessment.

Engineers identified the source of the leak as a broken air-conditioning unit drain line valve. According to the operator, the valve broke unexpectedly before the end of its projected three- to five-year operational lifespan.

Authorities confirmed that technicians have since replaced the defective component and subjected the train set to safety and maintenance checks before returning it to service.

To prevent similar issues, LRMC said it is cutting its inspection interval for AC drain valves in half — checking them every 5,000 kilometers instead of the manual-prescribed 10,000 kilometers.

The private operator added that it plans to replace the valves across the entire fleet over the long term.

LRMC affirmed its commitment to providing commuters with a safe, comfortable and reliable daily journey along LRT-1.