One of the advantages of window of model steel door is basic do not need to maintain, but considering profile of door of a lot of model steel door is chosen undeserved or process quality is poorer, suggest treasure friends so people better half an year to a year overhaul and maintain.  

General check the following aspects of u p v c window:  

1.door window frame, fan profile weld without cracks.  

2. there is no obvious deformation, warping, flat fan sagging.  

3. check the sealing strip, strip whether there is contraction, deformation, gap.  

4. hardware accessories are broken, damaged, tight.  

5. Whether the drainage hole is unobstructed.