Well, it's fixed. Here's the deal ...
Roto came out and determined it was the thermocouple. It's a Whirlpool and he said that is a constant problem with that brand and very typical. However, after taking the old thermocouple out, he realized Whirlpool does things 'different' and he didn't have the part. A trip to Lowes and some calls around ... and he couldn't get the part. So ... no hot water so far.
Next I called Dickerson plumbing and told them what was up. They said they had the part and could fix it ... so I said come on out. About an hour later they appeared and sure enough ... installed a new one and viola, we have flame!
HOWEVER ... and OF COURSE ... he looked at my unit right before he left and told me he couldn't leave with it running and was required to turn my gas off to the water heater. WHY? Because he said I had a unit that must be vented thru the ceiling/roof, however the configuration I had vented it thru the side wall. He told me I must either vent it up, or buy a new unit that was "direct" exhaust (something like that). So I let him leave, and I turned the gas back on and started it up myself. This might not be the smartest thing, but it's been working this way for 5 years (the age of the unit) and I've not had a problem. I keep a carbon monoxide detector in the garage and it doesn't register anything, so I assume there isn't much in the way or exhaust in the garage -- BUT the service tech STRONGLY felt that there would be and told me "everyone would die one night" if it leaked (hope not!)
What are your opinions? What's involved in venting it up? Should I be concerned?
And by the way ... Both companies charged an UNREASONABLE amount in my opinion ($160-$180) for about 20 minutes of work and one replacement part (the thermocouple).