If you're familiar with the work, loosen a union *after* the
furnace gas shutoff valve and allow enough air to escape.
If you're unfamiliar with the practice, ask the utility
to light the pilot; usually they are very co-operative.

So...I'm not encouraging you to do anything dangerous;
use your own good judgement.

im

Not sure I can get at that 1/2" black pipe, but did go after a thin line and
loosened it. No gas came out, as it's after the electronics, and I think
that's stopping the flow of gas.

I guess my next step is to call the gas company, and then later, the HVAC
technician.