Roger Mills wrote:

The spring winds up as the door *closes* so that it assists you to open it
against gravity. [The other way round, the door would come crashing down -
driven by the spring - and would be *very* hard to open because you would be
lifting it and winding up the spring at the same time.

If you can get at it, it's usually easiest to adjust the spring tension with
the door propped fully open

Thanks for the response Roger. I understand that the spring needs to be
at minimum tension when the door is open and maximum tension when the
door is down, however with the spring at zero tension (the current
state), you can wind it in either direction and it will spring back to
the current state. The winding cones should indicate which direction the
spring needs to be wound in, but the new cones appear to be colour coded
the opposite way around to the old ones. Once I've established which way
the spring winds, I'll then fit the cones to suit.

If I wind the spring one way, the coils tighten and the spring gets
shorter, if I wind the spring the other way the coils open out. From a
quick google it seems that the coils opening out is the correct
direction, I'm just looking for confirmation that I have understood this
correctly.

Thanks

Chris

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