For correct operation the touchscreen must be close to the protective glass but not pushing hard against it.
If it is pushing too hard against the glass false touchscreen presses can be detected, or the protective glass could be pushed out of the bezel. If the touchscreen is too far away from the protective glass it will be insensitive to presses.
The PDF document, including images and diagrams, shows how to check and solve this.
WARNING: Any maintenance work undertaken on a James Heal instrument must be done so by a trained and competent person. Where electrical work is detailed, this should only be completed by a qualified engineer. James Heal is not responsible for damage or injury arising from work carried out by any person not qualified to do so. If in doubt, please contact James Heal or your local James Heal Agent.