When Dometic had the recall a few years ago due to fires, a guy on one of the RV forums had a good write up. He was a RV repairman. He said Dometic changed the spec on the thermocouple to make them heat up quicker so the would cool faster. He said the faster heating, cooling caused the tubing to expand, retract more causing work hardening fractures. My thermocouple was out of spec, so it was replaced at my expense. If I can find the specs I will post them.