Hydraulic Jack Replacement in a Community Hall
You are called to a 2-stop hydraulic elevator in a 40-year-old community hall. The car is rated 1360 kg, travels 4.2 m, and the jack is a single-stage in-ground cylinder inside a PVC casing. The pit has about 25 mm of oil/water emulsion and the sump pump is not working. The owner reports the car “sinks about 100 mm overnight” and has been leveled repeatedly by maintenance. You find the jack packing leaking, the cylinder nameplate unreadable, and no oil containment. The owner has a quotation from a contractor to “replace the jack with a like-for-like unit next week” and asks whether the elevator can stay running until then. The car currently levels and runs, but the relief-valve setting is unknown.
1. Is replacing the jack maintenance or an alteration? What must happen before work starts?
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Replacing the jack or cylinder is not routine maintenance. It changes a major component of the elevating device and is treated as an alteration under the Ontario elevating-devices regime. The work therefore requires TSSA approval before it begins, with the required drawings and specifications, and it must be done by a licensed contractor. “Like-for-like” does not exempt the work. The submission should identify the cylinder, casing, oil containment, relief valve, and any changes to the hydraulic system. I would tell the owner not to schedule the contractor until the approval is in place. Separately, the oil in the pit is an environmental and slip hazard; the source must be found and the pit cleaned, and any spill reporting obligation should be checked. Starting the replacement without approval risks an order, failed inspection, and a system that cannot be accepted.
2. Can the elevator remain in service until next week? Justify your answer.
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I would not accept continued passenger service on these facts. A hydraulic elevator should hold its position; sinking 100 mm overnight indicates a leaking cylinder, a leaking valve, or both. The packing leak and oil in the pit support that conclusion. The relief-valve setting is unknown, so I cannot confirm that the system is protected against overpressure. The car may also drift with the doors open or stop below floor level, creating a trip and entrapment hazard. The fact that it “runs and levels” does not make it safe. I would remove it from service, barricade the entrance, place a tag, and tell the owner in writing. I would not simply add oil or increase leveling frequency. The pit should be pumped and cleaned, the sump repaired, and the jack replacement completed under permit before the car is returned to service.
3. What tests and inspections should be completed after the new jack is installed?
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After installation, verify that the cylinder, casing, and oil containment match the approved submission. Pressure-test the hydraulic system as required by the adopted code, set and confirm the relief valve, and check for leakage at the jack, fittings, and valve. Operate the car through full travel and check leveling, lowering, and stopping performance with rated load. Confirm that the pit is dry, the sump works, and no oil can reach the soil or pit floor. Check that the jack is properly supported and that the casing is intact. The TSSA inspector must inspect the alteration before the car is placed back in service. Record the pressure-test results, relief-valve setting, oil quantity, and any deficiencies. Return to service only after the approval, inspection, and corrected deficiencies are documented.