The Atlantic hurricane season runs from June 1 to November 30, and its peak comes around September 10. Long power cuts are part of planning for it in South Florida. People think about water, fuel and phone chargers. The garage door is easy to forget until the car is inside and the power is off.
A battery backup lets the opener keep working for a while after the power fails. It is a simple device, but it only helps if you know what it can do and you have checked it before you need it.
How a battery backup works
The backup is a rechargeable battery that sits inside the opener's motor head or in a small separate case wired to it. While the power is on, the opener keeps the battery topped up. When the power drops, the opener switches over to the battery on its own, with no button to press.
Openers built for battery backup use a DC motor, which runs well on battery power. Most units slow the door down and turn off the opener light while on battery, to stretch the charge. Many also beep or flash to tell you they are running on the battery.
A battery gives a limited number of open-and-close cycles before it runs flat. The opener's manual lists what to expect for that model. Treat it as enough to get the car out and back in once or twice, not as a way to use the door normally for days.
Testing it before the season starts
Batteries age even when they are not used. A backup that worked fine two years ago may barely move the door now. A quick test in late spring, before June 1, tells you where you stand.
- Make sure the area under the door is clear and nobody is nearby.
- Unplug the opener from the ceiling outlet.
- Open and close the door with the wall button or a remote.
- Watch and listen. The door should move smoothly, if a little slower than usual.
- Plug the opener back in and confirm it shows the battery is charging.
If the door struggles, stops partway or the opener warns of a low battery, replace the battery now rather than waiting for a storm. Use the replacement battery the manufacturer specifies for that opener. Many manuals also give a suggested replacement interval, which is worth writing on the battery case with a marker.
Summer storms bring another risk to the same opener. A nearby strike can damage its electronics, and our article on openers hit by a lightning surge explains what fails and how to protect it.
What a backup cannot do
It cannot fix a door that won't move
The battery powers the motor, not the springs. If a spring or cable fails during the storm, the backup cannot lift the door, and trying will only strain the opener.
It does not make it safe to open during high wind
A garage door is one of the largest openings in a house. Opening it while strong winds are blowing can let wind pressure into the garage. Keep the door closed while the storm is passing, and use the backup for after it, when you need to get the car out.
It will eventually run flat
When the battery is empty, the door goes back to manual. Know where the red emergency release cord is, and practise using it once on a calm day so you are not learning in the dark. Re-engage the trolley when power returns so the opener can control the door again.
Adding backup to an older opener
Some openers accept a backup battery kit as an add-on. Others, particularly older AC-motor chain drives, were never designed for one. If yours can't take a battery, the choice is between relying on the manual release during outages or replacing the opener with a model that has a backup built in. Our garage door opener repair page covers how openers are assessed and when replacement makes more sense than repair.
Notes for Aventura homes
Aventura is mostly high-rise condominiums, and those buildings' shared garages are run by their associations. A personal battery backup matters most in the city's smaller pockets of single-family houses and townhouses with their own garages. The largest share of the city's homes was built in the 1980s, so an opener that has never been replaced may be old enough that adding backup means a new unit.
Our Aventura garage door repair page explains how NovaLift Garage Doors serves homeowners there from Hollywood. To check whether your opener can take a battery backup before the next storm season, call (954) 758-9013.