Mobile Home water heater model #MFG1F4040T3PV7K

Just barely year old. Last 6 weeks, goes off. Did every 2 weeks then every one week, now every couple of days. I light it and turn it up and down; seems fine.

I had a whirlpool and it did the same thing. Tech finally changed gas valve and it has been ok for 1 year. Apparently these all-enclosed ones seem to do this after a year...

Tech looked at it and seems to think burner and gas valve faulty. Universal gas valve doesn't seem to work; something about a left thread difference(?). Help!