Why is my rolling security grille stuck?

A grille that worked last night and will not move this morning is usually telling you one of a few things. Here is how to tell which one, what staff can safely check, and when to stop and call.

What is a rolling security grille?

A rolling security grille is a coiling door made of open links or rods instead of solid slats. It rolls up around a spring-loaded barrel above the opening and rides down in a guide on each side, the same way a rolling steel door does. Stores in malls, pharmacies, parking garages and storefronts use grilles because the space stays secure after hours while light, air and sight lines pass through. A counter shutter works the same way, with solid slats over a service window.

Start with how it is stuck

Where and how the grille stops points to the cause.

• Too heavy to lift, but it comes down easily. The spring in the barrel has lost tension or broken. DASMA, the door industry's trade group, says a rolling door should be easy to move near the open and closed positions, needs more force through the middle, and should stay open on its own. A grille that has to be propped open needs service.
• Stuck halfway, or stops at the same spot every time. Something is catching: a bent guide, a bent row of links or rods, or debris packed in the guide.
• Rubs, scrapes or leans to one side. A guide has been knocked out of line, or the bottom bar is twisted, so the curtain binds on one side.
• Comes down but will not lock. The bottom bar no longer sits flat, the slide bolt or lock is bent, or the grille is not coming all the way down.
• Will not roll up tight, or creeps back down. Too little spring tension, or a guide stop or bent link catching near the top.
• A motorized grille hums, stops, or runs one way only. The problem may be the operator, its brake or limits, or the grille itself jamming.

Why a rolling security grille gets stuck

• Bent or dirty guides. Carts, hand trucks and cars bump the guides, and grit, trash and leaves pack into them. DASMA's checklist says the guide gap must be even from top to bottom and a bent guide must not bind the curtain or bottom bar.
• Bent links, rods or slats. A hit or a forced entry bends a few rows, and the bent row catches in the guide or in the coil.
• Spring tension. The springs inside the barrel do most of the lifting. As they tire, the grille gets heavier and may not stay up. A broken spring makes it feel like dead weight.
• A twisted bottom bar or a bent lock. The curtain sits crooked, the lock will not line up, and the grille may stop short of the floor.
• Rubbing at the top. The curtain or grille rods rub the hood, the header or the bracket at the end of the barrel. DASMA lists that as a reason to call for service.
• The motor side. On a powered grille, Clopay's rolling grille manual lists a tripped breaker or thermal overload, a manual interlock left open, a slipping clutch, a broken drive chain or a brake that will not release among the reasons a grille will not run.

What you can safely check

1. Make sure every lock and slide bolt is fully open, and nothing is jammed in the bottom bar.
2. Look down both guides with a flashlight for trash, rocks or packed dirt, and clear what you can reach by hand.
3. Look at the curtain for a bent row of links or rods where it stops.
4. Check that the guides look straight and are still fastened to the wall.
5. On a powered grille, check the breaker, and make sure the manual chain or crank interlock is engaged the way the operator needs it. If the operator strains, DASMA suggests closing the grille with the operator, switching to manual, and calling for service if it takes too much force by hand.
6. Lift or lower slowly and evenly from the center of the bottom bar, never from one corner.

What not to do

Do not touch the tension wheel or the brackets at the ends of the barrel. DASMA warns that the brackets and counterbalance assembly are under extreme spring tension and could cause death or serious injury, and says to call for service if the spring needs adjusting. Clopay's manual adds: do not operate the door if it becomes jammed or broken. Do not force a stuck grille with a bar, a forklift or a vehicle, and do not keep running a motor against a jam. Forcing a grille usually turns a guide repair into new links, a new bottom bar or a damaged operator.

Keeping a grille from sticking

Clopay's maintenance schedule asks for a weekly look for damaged links or slats, hang-ups or jamming, odd noises and a lock that does not hold, a monthly check of the guides and their fasteners, and a quarterly check of the brackets and adjusting wheel. Keep the guides clean, lubricate the drive chain where there is one, and test any sensing edge. For grilles that run every day, a commercial maintenance plan catches these faults before closing time.

Common questions

Why won't my roll-up grille roll up tight?

Most often the spring has lost tension, so the coil does not wind fully and the grille slips back down a few inches. A guide stop or a bent link catching near the top can do the same. Retensioning the spring is a job for a trained technician.

How do I reset a roll-up grille?

A manual grille has nothing to reset. On a motorized grille, check the breaker, reset the thermal overload if the operator has one, and close the manual interlock. If it still will not run, or it runs and the grille does not move, call for service rather than resetting it again and again.

How can I troubleshoot a commercial roll-up grille?

Note where it stops and whether it is heavy, catching or leaning. Heavy all the way points to the spring, a stop at one spot points to a guide or a bent row, leaning points to a guide or the bottom bar, and a powered grille that will not run points to power, the interlock or the operator. Then use the safe checks above.

Can a stuck grille be repaired, or does it need replacing?

Most stuck grilles are repaired. Bent links, rods or slats are usually replaced in the damaged rows, guides are straightened or replaced, and springs are retensioned or replaced. A new grille makes sense when the curtain is bent across most of its height or the barrel and guides are worn out too.

How G Brothers helps

G Brothers installs and repairs rolling security grilles and counter shutters across the Denver metro, including Lakewood, Denver, Arvada and Wheat Ridge, manual and motorized, on any brand. We dispatch 24/7, our average response is about an hour and a half, we are members of the International Door Association, and we can provide a certificate of insurance, usually within 24 hours. See rolling security grille and counter shutter repair and roll up and rolling steel door repair, read about the rolling grille door, call (720) 421-6489, or ask for a free estimate.

Sources

• DASMA, Technical Data Sheet #270: Recommended Rolling Door Maintenance Practices for Building Maintenance Supervisors
• Clopay, Rolling grille installation manual (safety, maintenance schedule and operator troubleshooting)