Thanks once more. I did finally reach the auditor, who told me to look for a “pilot /on/off” knob at the “way top” of the heater. I didn’t find it there, but did find it where you said, on the top of the gas control. The heater is working now. I did the match test for back drafting, and it looks good to me; I’ll have my husband repeat it tonight and see if he agrees.
I have put maintenance for both our water heaters on my reasonably urgent “to-do” list. Things have been a bit hectic recently.
Thanks again for your help.