Flyscreens are low-maintenance, but "low" isn't "none." A five-minute check twice a year — start and end of the wet season is a good rule of thumb in South East Queensland — will add years to a set of screens.
Check the tracks
Grit and dust build up in sliding screen tracks and are the most common reason a smooth-running screen starts to stick. Vacuum the track with a brush attachment, then wipe it out with a damp cloth. Avoid oil-based lubricants — they attract more dust than they solve; a dry silicone spray on the rollers is a better bet if a screen is still sticking after cleaning.
Look for mesh sag or bowing
Humidity and heat can cause a frame to expand slightly over a Queensland summer. If you notice the mesh sagging or the frame bowing, it's worth getting it looked at before it gets to the point of pulling away from the frame channel — a small adjustment early is a lot cheaper than a re-mesh later.
Check the seals
Run a hand along the edges where the screen meets the frame. Gaps here are where insects actually get in, even with an intact mesh. Weather seals wear over time and are a simple, inexpensive replacement.
Wash the mesh
A soft brush and warm soapy water, rinsed off with a garden hose on a gentle setting, clears salt air residue and general grime without stretching the mesh. Avoid high-pressure washers directly on the mesh — the pressure can distort fine weaves over time.