Server Accessible Request for UltraVNC?

[NWilkes]

Morning all,
I have had a browse to see if there is some sort way of sending a request through UDP or other means to determine in the server is active but cannot find anything.

Issue;
We have a central production management system which controls process data etc to 100's of stations across multiple plants. We use the Command line in viewer to open a VNC session through our control system for support purposes, but sometimes the server is not responding (PC down, IT issue, or more commonly VNC not responding).
We already know whether the PC is accessible, but do not know if the VNC server is running / accessible, and often find out on a need to know basis which is generally too late on a JIT system. This then requires someone the other side to restart VNC / PC / or even re-install VNC in some cases which can lead to production stoppages.
Proposal;
Our system is regularly polling the PC's on the production line for data / connectivity, but is it possible to request a VNC server status, so we can have feedback to know whether there are any errors prior to actually needing to connect to the PCs via the viewer using UDP or something else?

Thanks in advance.