Chain tension on a operator is very critical to get proper life out of the operator and ensure that the operator is not excessively noisey.
It is rather simple to do. Somewhere along the chain their is some type of screw that allows you to either tighten or loosen the chain. On Chamberlain operators (also known as Liftmaster, craftsman, or accessmaster) the chain is attached to the screw that tightens or loosens the chain slack. On Genie (aka Overhead Door Co.) there is a screw that moves the pulley just above the door that you can adjust with an open ended 1/2" wrench.
It is important to note that the door should be disconnected during this procedure. The chain should be tight enough that it is not hanging more than say 1/2" (should be above bottom of trolley rail).
This is not to say the chain will not or should not slack when the door is run to the closed position. Certain manufacturers garage doors require more force to get the door to seal the floor. If you are having to max out the sensitivity settings to get the door to seal the floor (assuming door is already level) than you will probably will have some chain slack and maybe even some trolley arch.
need further assistance email me at
rreeson@tconl.com
ryan