One of those devices of daily life that we take for granted could be our garage door opener. Every morning, we press on the remote, the door opens, and we pull out of the garage. But did you ever stop to think exactly what goes into this operation?
Here are some fundamentals that will have you looking at your door opener differently the next time you go to use it, and hopefully appreciate it a little more and give it a little care.
There are different types of door openers
By far the majority of garage door openers in North American are central, meaning there is a trolley that pulls the door, driven by a motor of various lifting capacities, installed on the ceiling in the “center” of the door.
However, a change in recent years to higher and higher garage ceilings, such as cathedral types, has led to door openers being installed next to the door. These are called Jackshaft openers.
How does the signal transmitted from the remote control operate the door?
Basically, the system is a radio transmitter (the remote) and a radio receiver built into the opener. The remote sends a radio wave on a precise frequency, 315, 315 or 390 MHz, which is picked up by the receiver in the motor housing. This radio signal causes the door to open or close.
Often, garage door technicians need to explain this basic principle when homeowners call saying that they repeatedly press their remotes, but nothing happens. In properly understanding the concept transmitter – receiver, it becomes much easier to find the source of the problem. To answer this intriguing question, there are a couple common causes, most frequently being a dead battery in the remote or even simply a power outage in the neighborhood.
Pirating of signals: myth and reality
Now and then, people ask garage door professionals if it is possible that a plane passing over their house can open their garage door. That’s a myth! It is all a question of radio frequency, and door openers, like most other means of communication, operate using very precise wavelengths which are managed by government agencies.
Now the reality. If you have a door opener manufactured before 1993, it was made using a technology based on DIP switches (put in +, 0 or – positions). Although these remote controls have up to 8 positioning clips (in addition to +, 0, -), it can happen that a malicious person can pick up the signal and can open the garage door in your absence. But, let’s say the chances are very slim.
Since 1993, the company Chamberlain, which includes the LiftMaster and Craftsman brands, has used their SECURITY+ system that allows up to 1 billion possible codes. What’s more, each time a code is used, it is changed for the following time.
Another improvement came from Chamberlain in 2013, with the introduction of their MyQ system that allows you to open and close your garage door from your mobile phone, tablet or laptop.
And more recently, since August 2017, Chamberlain has added a Wi-Fi feature to some of its door openers. As you can see, it is becoming increasingly difficult to copy the open/close signal for your garage door opener.
The different types of drives
The most common door opener is a chain drive, using a chain similar to one on a bicycle (or a combination of chain and metal cable. Another oft-used system is belt drive which uses a rubber belt reinforced with steel, like that used for making car tires. This latter type of opener is much quieter than the chain drive. Last and least-used are openers that use a screw drive.
Nowadays, almost all AC‑type (alternating current) door openers are either ½ or ¾ HP. Also seen are DC‑type openers. One feature of DC motors is that their speed varies. They start slowly, increase to regular speed, then slow before stopping.
The strength of an AC motor cannot be compared to a DC motor. For an AC motor, strength is calculated in horsepower (HP) while DC motors are rated in Newtons.
An often overlooked fact that should be pointed out here is that a door opener is calibrated to lift up to 225 lb. (100 kg.). But it can also push down the same weight with equal strength. That is why every garage door professional will insist on telling you that your garage door must always be well balanced. What does that mean? If the spring system that acts as a counterweight to the total weight of the door is well calibrated and adjusted, the dead weight of your door will be around 8 to 10 lb. (4 to 5 kg). At that weight, opening your door with just one hand is to be expected.
Reversal systems: they must work correctly at all times!
Since 1993, it has been legislated that all door openers sold in North America must come equipped with two automatic reversal systems. The first one is mechanical: when the door is lowering, if the opener senses resistance, such as hitting an object or person, it must stop automatically and reverse direction.
The second system uses photo eyes. It consists of two small units, one on each side of the door, placed between 4 to 6 inches (10 to 15 cm) from the floor that act like store doors that open and close automatically. For a closing garage door, if the invisible beam of light between the two units is broken, the door must immediately reverse direction.
To learn more….
Contact us without hesitation, toll free at 1‑877‑794‑4223 We know all of this and more about garage doors and openers. We can advise you and explain the best choice to make in your situation while also respecting your budget. If you’d like, we can email you a quotation.
If it’s convenient for you, then stop by our showroom. A tool that is available for you is our design center to assist you in selecting the style that fits you best. For more inspiration, view the myriads of examples in our image gallery.