The patio door is about 15 years old and fitted with two GU bogies with a connecting rod between the two. The springs which 'throw' the door to the frame when the bogie hits the 'keeper' have broken. I have phoned a couple of local installers who only seem to want to fit a complete new frame and door. I have emailed upvc-hardware.com who have a picture of the bogies on their web site, alas, they say they have none left and unlikely to be getting any. Seems stupid to spend hundreds of pounds for a new frame and door .. just for a couple of springs oreven a couple of bogies!
Yes unfortunately GU have discontinued the old type of bogies (code 31472). At present, as far as I know nobody has manufactured or can supply replacement springs.
It is likely the only repair possible is to replace the bogies (runners) with the new type GU ones. The current GU bogies (code 38514) should work with the old track, however a new pack of covers (accessory pack) will be required. Here's a link to a company selling these parts on-line:
https://www.upvc-hardware.co.uk/patio-track-components/bogies/gu-tilt-slide-patio-bogie-wheels-38514
This is an old post now but I have just had a similar problem where the little spring had broken on the bogey. Quoted £800 for a 4 hour repair by one company with parts circa £200 - crazy for the sake of one spring. I found a replacement spring from this company for £10 and it has done the trick taking half an hour to fit! All you have to do is support the door, remove the bogey and thread the spring on.
www.upvcspares4repairs.co.uk
Very fast delivery as well
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