I recently had a similar problem with our electric awning. I seemed to be straining when retracting, thought the motor was failing. I needed some unrelated work done so had the service facility check it. It took only three turns on the spring and it work perfectly now. As in the warning above, don't mess with the spring tension unless you know what you are doing. Those springs are wound tight and can cause serious injury. Let someone who knows what they are doing have at it, money well spent and only takes a few minutes.