I have garage door with two springs. One of them has snapped and the door has been operating on only one spring for past month or so.
Do I need to replace the broken one or just carry one since it’s operating on one spring?
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Sign up to join this communityI have garage door with two springs. One of them has snapped and the door has been operating on only one spring for past month or so.
Do I need to replace the broken one or just carry one since it’s operating on one spring?
You must replace both springs.
Avoid using the door until you do. You must replace them with the correct springs which are color coded according to door weight. You must weigh your door and not rely on the old ones being correct.
If your springs are the kind hanging over the rails and stretch out straight when opened you must thread the retaining cables correctly, whether or not they are currently installed. Lots of YouTube tutorials on all this. Watch several. There are a lot of dangers to be aware of.
If your springs are coiled over the door frame they are even more dangerous and you should get a pro to do the work. It's not worth learning this once in 15 years skill given the dangers.
Close the door, then unhook the power garage door opener immediately! Start operating the door manually.
That will answer your question right away about whether the door is seriously broken. "Yes!"
Garage doors are dangerous. The door and the spring store a lot of energy and they can kill you. This is not for DIYing unless you learn the risks and take proper precautions.
The spring is really a counterweight. The door is supposed to feel weightless to the operator (you only have its mass to contend with). With half the spring gone, the door will "weigh" 50% of its actual weight. That means it will drop like a guillotine, with half the force it would drop with no spring at all. The only reason you don't know this is the power opener is hiding reality from you :)
There isn't extra spring there, it's not redundant or a backup. The spring must be balanced or the door would fly upwards. I had a door do that once when I set the spring too tight :)
Use the numbers on the old springs to order 2 new springs. The 2nd spring doesn't owe you anything. Replacing them is a bit of a job, the main thing is know what you're doing when winding and unwinding them.
Set the spring tension evenly so one spring isn't doing most of the work. The spring is correct when the door is happy in any position up or down. If near the bottom it creeps upward or downward, it's not set right yet.
Garage door sprigs are dangerous.
They have enough force to keep the door up, and garage doors are heavy, otherwise they would not need springs in the first place. You do not want a tensioned spring flying in your face when you do something wrong.
For your own safety, consider calling local shop that installs garage gates, they will be happy to install new springs for you. They are trained to do this, have access to parts, have proper tools, and know how to tune the tension so door opens flawlessly.
The door was designed to work with two springs to balance the lifting and lowering force. With just one spring, those forces are increased. If you have a garage door opener and it's still working, it will burn up faster. If the door is manually operated, it will be much harder to open and the weight when closing it could be dangerous. You need to have the springs replaced for safety reasons.
I'm mildly surprised that your door doesn't jam, since one side will tend to be lower than the other, due to some "play" in the joints... Also, if one broke, the other is soon to follow, so you might as well just have replacement episode, instead of two.
And, given my own experience, as in some other answers, doing it yourself is, first, dangerous, and, second, easy to mess up. :)
The purpose of the springs is to take the weight off the garage door motor. Disconnect the chain drive by pulling on the rope while holding the door from slamming down. Now try to lift/or lower the door with one hand. If you can not do it, your motor is suffering. If you are lucky and have strong motor like 3/4 HP (normal is 1/2 HP) it will handle it for a while.
Replacing the spring is not DIY work even if it looks simple. First you will need special tools for the tension adjustment. There is a lot of energy stored in the spring and it can kill you.
How it works (images from Amazon)
You should replace the broken one.
They are designed to operate as a pair, meaning the remaining spring is double-stressed at lifting the whole door by itself, or the one good spring is pulling on one side of the door, making the door lopsided as it goes up and down, leading to extra wear and further damage to the mechanism.