Home inspectors are meant to give you a general overview of the condition. They are not typically a specialist in any particular area of your home, like hvac, or plumbing, foundation or roofs. They dont open up walls or fix things just observe and report what they see. They will usually look at anything you ask them to on a property and at minimum give you a recommendation on who specializes in that area.
Typically, home inspectors are not allowed to do anything that would be considered intrusion. This can include tearing down sheetrock, removing appliances, digging or other actions that would be similar, unless the purchase agreement states differently.