Broken Mechanism On UPVC Window: What To Do? | Checkatrade
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Broken mechanism on uPVC window: what to do?

If your uPVC window handle moves but the window won’t open, this could be down to the mechanism being broken. Here, we’ll look at what to do if you have a broken mechanism on a uPVC window. But first…

How does the mechanism on a uPVC window work?

To understand how to fix the mechanism on your uPVC window, you’ll need to understand how it works.

When you close your window, it locks. There are a few different parts that work together to make this happen:

  • Handle
  • Gearbox
  • Shootbolts (or espagnolette)
  • Shootbolt roller cams (or mushroom)

Basically, when you turn the handle of your window, the gearbox (which is attached to the handle) pushes shootbolts and roller cams out in the furthermost corners of your window to lock it.

When parts of the gearbox break or the shootbolts seize up, this will stop your window from being able to open again.

How to open a uPVC window with a broken mechanism

If your window has jammed, you can follow these simple steps to open it. Just be aware that uPVC can be easily scratched or damaged. Plus, be careful not to drop anything out of the window while you’re working on it.

  1. Get your tools. You’ll need a pair of pliers and a thin tool that’s been bent at 90 degrees. This could be an allen key, pick or even a bent nail.
  2. Move the window handle to the open position. That way, any working shootbolts will be released.
  3. Insert the tool between the window and window frame. Insert it where the shootbolts are located – in the top or bottom corner of the window, on the edge where the handle is located.
  4. Push the tool towards the window handle. The aim is to try and hook the shootbolt roller cam, in order to free up the shootbolt. You should feel the tool stop when it makes contact with the shootbolt roller – pull it towards the window handle and it should release this side of the window.
  5. Repeat if necessary. If the other edge of your window is also jammed, repeat these steps at the opposite end of the window.

Voila! Your window should now open. However, it’s best not to close it again immediately as the mechanism will probably still be faulty and your window may get jammed shut again. Instead, you’ll need to deal with the underlying problem…

How to fix the broken mechanism

Now that you’ve managed to open your window, it’s time to fix it.

As a temporary fix, you might be able to simply refit the shootbolt gearbox without the shootbolts. That way, your window will still be able to close and lock (although only using the handle latch) while you wait for parts to arrive.

Alternatively, if you’re ready for a more permanent fix, there are a few routes you can take.

1. Clean the shootbolts and rollers

If your shootbolts and rollers have seized up, you may simply be able to free up the parts and clean them. Add plenty of lubricant to keep them in good working order. Silicone grease works particularly well for windows.

2. Replace the shootbolts and rollers

The shootbolts and rollers can become corroded over time. If you’ve cleaned the parts and they’re still in bad nick, it might be time to replace them as necessary.

3. Replace the window gearbox

If there’s a fracture within the gearbox, it’ll need replacing. Remove the window handle and loosen the shootbolts. You’ll then be able to slide the gearbox out.

When you insert the new gearbox, make sure you do it the right way round, otherwise it’ll change the direction that the window handle turns in.

4. Check the gearbox and shootbolts are connected

Sometimes, shootbolts can get disconnected from the gearbox. In this case, you’ll need to refit the gearbox, making sure that it lines up properly with the shootbolts and is secure.

Find the best window repair services near you

If all this sounds a little complicated to you – or you simply lack time and energy – why not get a professional window fitter to fix your window for you?

They’ll be able to tell you exactly what’s wrong with your window mechanism. And they’ll also be able to fix it to a standard that you can be confident will last for a long time to come.

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