What test can be done on a propane supplied furnance that has no propane?
Turn on the fan…
Yea, turning the fan on was the only thing I could think of
At the time of the inspection …
Why bother, it needs to have fuel, to be turned on to check for function. Write it up
Ditto. How can you inspect it if there is no fuel. All you can report on is any visible condition you see. Then write: have gas company fill the tank and have the system tested by a qualified contractor. Sure does limit your liability.