Arrived at location on 7/6/22 - Pilot was lit but thermostat was off. Turned thermostat on to 350 degrees. Fryer heated and cycled as should. Customer stated when fryer was running at 400 degrees then turned down it would shut off. Ordering a thermostat and high limit. Customer would like it switched out anywhere from 2:00 p.m. - 5:00 p.m. to avoid rush when parts come in. Returned to location on 7/12/22 - Drained unit upon arrival and shut fryer off. Tried to remove hi-limit and thermostat and both started to round off. Had to cut capillaries on both and remove with socket. Installed new hi-limit and thermostat with some thread seal. Refilled unit and started up. Cycled fryer a few times and checked for leaks. All okay.