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Why do I need a backup battery for my garage door opener?

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Why do I need a backup battery for my garage door opener?

Have you had any power failures in your area in the last couple of months? Has it happened a little more often than normal? As a precaution, did you know that you could equip your garage door opener with a backup battery for this type of situation?

It is just the thing when you need to get your car out of the garage during a power failure… So, what is this backup battery and what type of door opener can it be installed on?

Backup battery for garage door opener

What exactly is it?

First of all, it is a small, 12-volt battery unit that the opener uses for power when an outage occurs. Many brands of door openers provide this option: LiftMaster / Chamberlain / Mastercraft, as well as Genie and Linear. LiftMaster has had this option since 2003, so if you have this brand and it was manufactured after this date, you can add one to your current door opener.

For LiftMaster’s professional series models of openers, there are some with the battery (485LM) incorporated in the motor housing, like models 8550 and 8550W, and some where the battery (475LM) is over the housing, as the models 2500, 3800, 8500, 8360 and 8360W.

In the models where the battery is inserted in the motor housing, its size is approximately 3 ½” x 4″ x 2 ¾” (9 x 20 x 7 cm). When the battery is installed over the motor, its size is 12″ x 8″ x 5 ½” (31 x 21 x 14 cm). Note that one brand of battery cannot be used with another brand of door opener.

Other interesting features of these batteries

  • Once there is an outage, a fully charged battery is designed to supply a door opener with 24 hours of standby power during which it can operate up to 20 full cycles (1 cycle=1 open and 1 close) at an ambient temperature of 60° to 70° F (15° to 25°C).
  • They recharge in 4&bnbsp;½ hours.
  • They can be recycled like many other types of batteries.

How to know when it’s time to change the battery

Depending on the battery model you use, you’ll hear a beep every 2 or 30 seconds in addition to seeing an orange or red light indicating the state of the battery. The best approach is to go to LiftMaster’s website and read the instructions about the battery closely.


Is it very expensive?

If you want to add a battery such as the 475LM to your present door opener, budget about $100. If you are wondering how much it costs for a battery like the 485LM incorporated into the motor housing, you can estimate $50 to $60 over a door opener without a battery.


What if don’t choose the optional backup battery when I buy my opener?

The remaining option when power is disrupted is to open the door manually. You have to pull down on the red emergency release cord on the door opener, which disengages the trolley, manually lift the door, move your car out of the garage, then close the door and reengage the trolley by reconnecting it to the release mechanism. If you choose not to or forget to reconnect the trolley, anyone can open your garage door manually, meaning your possessions are no longer secure.

To avoid this situation, a side lock can be installed on the inside of the door on the second section. By pushing the steel bar on the lock into the vertical track, you’ll lock your door so that no one can enter. When power is restored, don’t forget to unlock this lock and reengage your opener.



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