Commercial Garage Door Won't Open: Fast Checks for Business Owners

Power and controls

Commercial operators are usually hard-wired to a dedicated circuit with three-button control stations, so the failure points differ from residential.

• Check the breaker panel for a tripped circuit serving the operator.
• Confirm the disconnect switch near the operator has not been left off.
• Test each control station — a failed open button on one station is common.
• Look for a key-switch or lockout left in the locked position after hours.
• On three-phase operators, a blown single fuse causes a hum with no movement.

Safety devices and interlocks

Commercial doors carry more safety hardware than residential ones, and any one of them will hold the door.

• Photo eyes across the opening, often blocked by pallets or a parked forklift.
• A safety edge or pneumatic bottom sensor damaged by an impact.
• A dock leveler or truck restraint interlock preventing operation.
• Fire-door release triggered by heat or a false alarm — this requires reset by a qualified technician.
• Timer-to-close or loop detectors on drive-through doors.

Mechanical faults on rolling steel and sectional doors

Rolling steel doors fail differently from sectional. On a rolling door, look for a slat that has walked out of the guide, a bent bottom bar, or a broken counterbalance spring inside the barrel. On a sectional, check for a broken high-cycle spring, a cable off the drum, or a chain hoist left engaged.

Do not attempt to force a rolling door up by hand — the counterbalance is inside the barrel and its failure is not visible from the floor.

Reducing downtime next time

High-cycle springs, impact-resistant bottom bars, guarded photo eyes and a scheduled maintenance interval based on daily cycle count are what separate a door that runs for years from one that generates emergency calls. Doors cycling more than 20 times a day should be inspected quarterly rather than annually.