• In broad general terms, any part of the uPVC double glazed window that is visible when the windows are closed should receive a wash twice yearly.  This can be done with a warm soapy solution, taking care not to use abrasive materials such as scouring pads, or abrasive cleaning solutions such as ammonia based cleansers. It is always a good idea to remove such items as jewellery and watches, before commencing cleaning work on uPVC double glazed windows as this avoids unnecessary damage (to the jewellery and to the windows!).
• here are also the options of installing windows with self-cleaning glass, such as ‘St. Gobain Bio Clean’ and ‘Pilkington Activ’.
  

  WD-40 Spray Applicator (click on image for details)

• When the windows are open, the remaining parts such as double glazed uPVC window locks, that you can then see should receive a wipe to remove dead insects, cobwebs, old oil or lubricants.  The use of a vacuum cleaner can be helpful in these situations.
• Always keep any drainage holes clear as this will ensure that any build up of condensation inside will be removed.

• All hinges and locking points should be kept clean.  This applies to uPVC double glazing windows and doors also. As with any metal moving mechanism, regular application of a light lubricant oil will help to keep these parts in good working order.  WD-40 spray is ideal for such tasks.  A light application of a product such as petroleum jelly to hinges and moving parts after lubrication will help ensure their protection.  Perhaps avoid heavier grease lubricants and avoid too much application that can result in grease oozing to the frames. It is always a good idea while cleaning to check the tightness of any visible screws at this time. Avoid getting grease or oil on curtains or window valances when you are carrying out this work.
• Clean the gaskets, weather strips and seals regularly with mild non-abrasive detergents.  While you are cleaning, inspect to ensure that all seals remain correctly fitted to the frames.  Many gaskets and seals can be removed and replaced without the complete removal of the window.  If seals or gaskets do need to be repaired, the task should probably be carried out by a trained maintenance person.
• If your frames of your windows suffer a small mark or scratch, repair kits can be available from upvc windows online suppliers, however it is best to avoid damage of the frames, as larger marks cannot be repaired.  Special care is needed if you are installing uPVC double glazed windows yourself.

Related posts:

1. Cleaning uPVC Doors And Windows.
2. Replacing Original Double Glazed Sash Windows
3. The Advantages of Installing uPVC Windows