Q. I just replaced a garage door spring that broke. My garage doors are only seven years old, and this is the first time that anything has broken. I knew that I had to replace both springs on the garage door, and I also knew that I had to weigh the door (without the springs) to get an accurate idea of the type of spring replacement that I needed. My door weighs 110 pounds according to the bathroom scale. Home Depot carries replacement springs that are all similar in length, about 25 inches. The replacement spring to buy is the one that is needed to lift the weight of your garage door. In this case I purchased a set of springs rated at 120 pounds each. This would be enough to lift my 110 pound door.
I have installed the springs and they seem to work fine, my only question is in regard to the safe stretch of the springs. The package that the springs came in says maximum safe stretch is 42 inches, which isn't much more than the non-stretch length of 25 inches. However, my springs are stretched roughly 55 - 60 inches, and stretch just as far as the springs on my other garage door do. Do I need to release the door cables so that the tension on the springs is reduced to the safe stretch of 42 inches? If so, I will do this on both garage doors.
A. The type of garage door spring you just replaced is called an extension spring. The rating of the safe stretch of any garage door spring will be a function of the material from which it was made. Of course itís going to be steel but not all steel is the same. Without going into a lot of detail about spring manufacture, my best advice about any installation of any manufactured product, whether itís a relatively simple device, like a garage door spring, or something as sophisticated as a gas furnace, is to always read, believe and follow the directions and warnings that accompany the device and donít vary or get creative. Thatís is such a strong building maxim that when something is installed in a home the manufacturerís directions for installation become the governing building code for that installation.
You wisely replaced both springs on a door that had just the one spring break so you avoided a potential tension mismatch between the two. But now you need to do a couple of additional things to make sure the job is done correctly.
You need to ďbalanceĒ the door so that as you pull the door up, or down, you can stop at any point and the door will stay put where youíve stopped and you can take your hand off the handle. And most importantly you need to install a safety cable inside o f the spring, attached to the tethering hardware at each end of the spring, so that should the spring ever let go it will be contained by the cable and not fly off with deadly force. As you know, when a garage door is in the closed position the springs a re in tension, like a stretched rubber band. If the metal gets tired or if there exists a slight flaw in the steel that permits the tension to break the spring and it flies off, you donít want to be anywhere near it. With the safety cable it will only startle you should it happen.
The other type of garage door spring is called a torsion spring and youíll see those mounted above the door flat on the wall in which the door is installed. If one of those breaks my advice is to call in a professional. Iíve heard that sky-diving is saf er than trying to replace one of those on your own and I know someone who lost a finger doing it.
If you now hook the door up to an automatic door opener, make sure it reverses when it hits an object close to the floor like a 2 x 4 on the flat. Grabbing it with your arm or sticking the recycling bin under the door wonít do. And electric eyes donít c ount for this test. It must reverse direction under this test or itís a potential killer. More than 60 children have lost their lives since 1982, killed by garage doors. Pre-1982 door openers should be tossed out. They are unsafe. Modern door openers should be tested frequently (monthly) to ensure that the reversing feature hasnít gone out of calibration.
You see, just replacing that spring isnít the whole story.