170,000 btu dayton torpedo heater oil fired, it shuts down after about an hour, I replaced the photocell in it and it still is showing e1 code is the over heat sensor bad??

SOURCE: wat the hell is wrong

Most use a spark plug to ignite fuel it could need cleaning. You also could have water in fuel or dirt
check and clean ignitor/spark plug clean fuel line and nozzle, drain and clean tank Check for water in fuel by tilting unit to have a low corner siphon fuel from that corner after 1 hr inspect for water.