A head of IT doesn't necessarily have to run projects, let along write code. What they do have to do is understand the business and IT well enough engage senior managers and set a direction that moves the organisation forward and improves efficiency. Once the direction is set your head needs to have the soft skills to get people aligned with it.
The key skills are the ability to communicate (at every level), set a clear direction, motivate and develop people, build a strong organisation. Somewhere in that strong organisation there needs to be people who create processes (ITSM) and know how to run projects (programme office).
Among other things I'd be inclined to do is assess staff satisfaction in the IT department. Very broadly, if they are hate their jobs and their bosses it's extremely likely that they have poor leadership.
This is a bit different if the organisation is small (rather than medium), of course.