*microwaves.

Nah it’s just an extractor fan. HVAC is a generalised term for Heating, Ventilation, Air Conditioning. Which can be a whole bunch of systems. As for can the shower damage it? Yes, yes it can. I’d move the PC as far away from the shower as possible. Turn down the shower temperature as then there will be less water vapour. Use some silica desiccant moisture traps around the PC also.