I ordered this replacement thermostat AFTER ordering the wrong one first. I removed the old thermostat and saw the model number and was able to immediately order the right one. The way the water heater was positioned, I had no way of seeing the model number until the new (WRONG) thermostat arrived and I removed the old one. The new one came in and is a DIRECT replacement for a State GS630YORT. I installed it but the water heater worked for about 30 minutes then quit. I then ordered a replacement burner assembly and it worked for about 30 minutes then quit. Before all of this, 2 months ago I replaced the thermocouple and it worked for about 30 minutes as well and quit. After basically replacing every main component of the water heater except for the tank, I was about ready to give up. I called a coworker and after telling him my flame started burning blue then went ALL orange, he told be to clean this filter/screen that's located at the bottom of the combustion chamber just underneath the burner because it seems as though it wasn't getting sufficient air. I removed the burner, got an old toothbrush and some paper towels and cleaned that filter (looks somewhat like a transmission filter) and brushed any dust that may have accumulated at the bottom of the chamber and then used a slightly damp paper towel to wipe up any remaining dust from the filter/screen itself and the area around it. I put the burner assembly back in and the pilot still wouldn't light. I noticed a little black dot in the center of what I call a thermal fuse of some sort (it's located on the right side of the burner assembly, it's white and circular and has 2 terminal blades to slide the 2 red wires onto) and I pressed it. I figured, it's not working so I can't do much more damage and when I did, I felt the slightest click and when I released that gas valve (trying to light the pilot) it STAYED LIT! I then turned the burner to the "A" (little hotter than recommended temperature) and monitored it for about an hour and noticed my flame was burning blue with just occasional hints of orange. After about 20-25 minutes the burner went out but the pilot stayed lit! I ran hot water for a while to drop the temperature to see if it would call for the burner and IT DID! This was 5 days ago and it's been going good since! I hope this helps anyone that may be having an issue they can't resolve with their water heater. Check the filter underneath the burner to make sure it isn't dirty or clogged before ordering $250-$300 worth of replacement parts like I did! Good luck!
