120 lb springs too strong for 120 lb door

[Venkman]

I have a 7'x8' steel clad (both sides) insulated Clopay garage door with 4 single pane windows at the top.

I replaced the original extension springs with the same weight rating, 90 lbs (light blue paint) about 10 years ago after one broke. I have noticed over the years that the door is quite heavy to lift with the opener disconnected. This is putting a lot of strain on the opener.

The door balanced at about 3 1/2 feet with the but fell quite rapidly below that. The lift force needed to raise the door off the floor, with the springs helping, was around 41 lbs.

So I weighed the door and was surprised to find it weighed 120 lbs!

According to all the charts online that weight and size door needed 25-42-120 springs (green color).
I put on the 120lb springs and now the door comes off the floor and won't stay closed. It takes about 18 lbs of force to keep the door closed.

So the question is should I use 110lb springs, even though the door weighs 120 lbs?

[FatimaandAhmed]

Hi Venkman!

It sounds like your door balance is off because the 120 lb springs are too strong, which is causing the door to float or not stay closed properly. Trying 110 lb springs could be a good next step to better match the door's weight of 120 lbs. After you install the 110 lb springs, test how the door balances; it should lift with minimal effort and stay in place without needing excessive force. Also, make sure everything else, like the tracks and rollers, is in good shape.

Let me know if you need any further assistance, thank you!