I had a spring break on my extension spring garage door. I'm trying to figure out what weight replacement spring to get without being able to fully weigh it. Basically, I'm afraid to take the other spring off and lower it, because I don't think I can pull it back up on my own, and I want to order the parts today.
The springs that were on there were 180#. However, they were stretched about 50% more than their max stretch rating. So I am assuming they were slightly underpowered. OR - is it possible that springs would stretch out that much prior to breaking if they were very old? I have no idea what the age is, but the tags on them seemed fairly rusty and I think they are pretty old.
I used an online calculator, which told me a non insulated steel door that is 16' X 7' is about 220lbs usually. This is 40# more than the springs that were present. I'm wondering if the reason the springs were so stretched out is that they were underpowered. I was considering going up 10lbs to a 190# spring with the assumption that that was the problem. Will that be an issue if the door actually weighs 180? Wouldn't I be able to adjust the heavier springs (by increasing the pull cable distance) so that 190 would work on a 180 door? Or do you recommend sticking with 180# springs?