If the handle on your UPVC door is not returning to the horizontal position it is probable that the spring cassette has failed in one or both of the door handles. Replacing the cassette is easy - simply unscrew the handle from the door, remove the old cassette and replace it with a new one. When choosing the correct type always measure the old cassette before ordering. Different models of handle from the same manufacturer can often use different types of spring cassettes, so you cannot be sure without looking first. Check the replacement cassette does not foul anything else in the handle (eg. fixing screws).
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