We may have found other answers which could help you.
Click here for Open Back DoorVelux KEM 140 skylight elec. opener only workd intermittent?
Velux skylight?
How can I mend the broken cord on my velux skylight?
Can you open a double glazed upvc window?
How can I fix my kacher window vac?
Hinge creaks on compositie exterior door?