Maintenance of WLAB2 vacuum toilets

Unstad was engaged to evaluate and improve the maintenance conditions for WLAB2 vacuum toilets across multiple passenger coaches. The objective was to identify the causes of high maintenance demand and frequent failures, and to establish measures that increase reliability, hygiene, and passenger comfort. The systems are older and had, over time, been affected by outdated documentation, discontinued components, and a lack of preventive maintenance.

Unstad carried out detailed inspections of critical components and associated pipework and connection systems, including drain valves, pilot valves, check valves, and hoses. The inspection revealed that several components—including solenoid valves, flush nozzles, and actuation/trigger systems—were incorrectly installed or misconfigured due to inadequate installation instructions. This contributed to recurring faults, inefficient operation, and unnecessary strain on the system.

Based on the findings, Unstad recommended revising the maintenance baseline with updated installation and configuration guidelines, targeted training, and an improved preventive maintenance strategy for wear-prone parts. These measures provided the client with a practical foundation to reduce reactive maintenance, increase system reliability, and ensure improved comfort and hygiene for passengers.