[homerepairguy]

There are 2 types of springs- extention and torsion. Extension are singles or doubles on each side track for the door. They are rated and usually color coded on the ends for the appropriate spring (ie green, red, black, etc.) The total weight of the door is evenly dispersed among the number of springs. The tension or pull on the spring is determined by the length of cable attaced to the spring(s). If the sides are not equal one side will pull quicker, it should be obvious which side goes up first. Lengthen that cable or shorten the slower to respond side. Sometimes this takes several attempts until it equals itself out. If the springs aren't matched this may not be possible. A green on one side will not match a red on the other. Torsion usually aren't a problem because the pair of cables are made to a specific length. They either have enough tension or don't. Either way the springs are to take the door up, NOT the opener. The opener is an initiator not a pulling device. It also controls the even speed ascent of the door.