Why Your Garage Won't Close All The Way When It Dips Below Freezing

Cold weather can create numerous problems for houses, but it can affect garage doors as well. Sometimes ice and snow accumulate where the driveway and garage door meet, causing the garage door to freeze shut. Ice between the door panels might also prevent the door from opening. Other times, the garage door opens just fine in sub-freezing temps and even starts to close, but then it immediately stops or lifts back up. This issue likely stems from safety sensors malfunctioning because of the cold.

Safety sensors use an infrared beam to prevent garage doors from closing on objects, people, or pets that may be in the path. Each garage door has one of these sensors on either side of the opening parallel to each other, about 6 inches above the floor. They essentially communicate with each other; one must be able to "see" the other for the door to close. The beam operates as a tripwire, so if something interrupts the line of communication (the beam), the door will stop its downward movement and reverse to the open position.

Plunging temperatures can cause condensation to accumulate on these sensors. This moisture interrupts the beam, while the cold temperatures may also cause the sensors to become misaligned as a result of the metal contracting. Sensor misalignment is one of the common reasons that prevents a garage door from closing. The good news is that you may be able to resolve the issue yourself with a few easy steps.

If the garage door fails to close completely when you use the remote, try pressing the wall button. Sometimes the wall button operates successfully even if the remote doesn't. The wall switch overrides the safety sensors, so if it works but the remote does not, condensation buildup on the censors could be the culprit. 

Any obstruction to the infrared beam prevents the door from closing completely. You may see it move about an inch, but it won't close any more than that. If condensation is the obstruction, take a dry cloth and wipe the glass portion of each sensor to remove the moisture. Be careful not to move the black boxes in the process, as doing so may misalign the sensors. Press the remote or wall button again to close the door and see how it responds.

If the door still fails to close all the way, the sensors are likely not aligned properly. You can realign the garage door sensors yourself by moving the black boxes until they appear to be parallel with each other and the ground; just be sure to turn the garage door power off first. As a safer alternative, contact a garage door technician for further assistance.