Garage Door Repair Glossary

This garage-door glossary is your quick-reference cheat sheet for the 12 most common terms Pasadena homeowners ask about when their wood-and-brick garage door starts to sag, squeak, or refuse to stay down. Print it, bookmark it, and you’ll know exactly what your technician means when they say “torsion spring” or “photo-eye sensor.”

Garage doors in older Pasadena homes—especially those with original brick facades or masonry walls—wear differently than newer tract-house models. If your 1920s carriage door is suddenly loud, uneven, or letting in dust from Colorado Street’s spring winds, you’ll want to speak the same language as the technician who arrives in our branded truck. Learn about our full service list or request a free estimate before the next Santa Ana wind kicks up.

Torsion spring

A tightly wound metal coil mounted above the garage door that counterbalances the door’s weight, letting it open and close smoothly. Unlike older extension springs, torsion springs last longer and handle heavier wood or carriage-style doors common in Pasadena’s historic neighborhoods. If one snaps, the door can drop suddenly—always call a pro to replace it. See our full list of services.

Extension spring

A long, stretched spring running parallel to the door tracks that helps lift the door by extending and contracting. Found on lighter-weight doors and some older Pasadena homes. They’re cheaper but wear faster than torsion springs and can snap with a loud bang—always replace both springs at once to keep the door balanced.

Track

The vertical and horizontal metal rails that guide the door up and down. In Pasadena’s older homes, tracks can bend or corrode over decades of use, causing the door to jump off the rollers or refuse to close. Bent tracks must be professionally straightened or replaced to prevent further damage.

Roller

Small wheels—usually nylon or steel—that ride inside the tracks and carry the door’s weight as it moves. Worn or cracked rollers make a grinding noise and can derail the door. In older Pasadena homes, rollers often seize from years of grit and lack of lubrication, so inspect them every spring.

Opener

The electric motor that automates your garage door’s movement. Modern openers have smart features like Wi-Fi control, but Pasadena’s power surges can fry older units. If your opener clicks but the door doesn’t move, the motor may be overheated—give it 15 minutes to cool before calling for service.

Photo-eye sensor

Safety beams mounted near the bottom of the door that detect obstructions and stop the door from closing. If they’re misaligned or dirty, the door may reverse unexpectedly. In Pasadena’s bright sunlight, sensors can also be blinded by glare—keep them clean and check alignment every season.

Limit switch

The electronic stop-points that tell the opener when the door is fully open or closed. If the switch is set too short, the door won’t close completely; too long, and it can slam into the opener. In older Pasadena homes, these switches can drift with age, causing erratic behavior.

Weatherstripping

The flexible rubber or vinyl seal along the door edges that blocks drafts, dust, and moisture. In Pasadena’s Mediterranean climate, cracked weatherstripping lets in hot afternoon air and smog particles. Replace it every 2–3 years to keep your garage—and the rooms above it—cooler and cleaner.

R-value (insulation)

A measure of how well garage door insulation resists heat flow. Pasadena’s brick homes lose energy fast through uninsulated garage doors. A door with R-12 insulation keeps the garage 10–15°F cooler in summer and warmer in winter, cutting HVAC costs. Learn how to add a liner for historic homes.

Cable drum

The grooved pulley at the end of the torsion spring shaft that winds and unwinds the lift cables. If the drum is cracked or the cable jumps off, the door can drop suddenly. In older Pasadena homes, drums corrode from moisture seeping under the door, so inspect them during annual maintenance.

Bottom seal

The thick rubber strip at the bottom of the door that seals against the driveway. It keeps out water, pests, and leaves—critical in Pasadena’s wet winters. A worn seal lets water pool under the door, rotting wood and brick. Replace it if you see daylight or water seeping underneath.

Travel module

The electronic brain inside newer garage-door openers that controls speed, force, and safety features. If your opener beeps but won’t move, the travel module may have tripped due to an obstruction or power surge. In Pasadena’s older homes, power fluctuations can corrupt the module’s settings—resetting it often fixes the issue.

Trolley

The part of the opener that connects the motor to the door, pulling it along the tracks. If the trolley is bent or the chain is loose, the door jerks or won’t open fully. In older Pasadena homes, trolley arms can sag from years of use, so check for play during routine maintenance.

Manual release

A red handle or cord inside the garage that disconnects the door from the opener, letting you open or close it by hand in a power outage. If your manual release is stuck or the door won’t stay disconnected, the release cable may be frayed—always test it twice a year to ensure it works when you need it most.

Frequently Asked Questions