I have a reddy heater. I have a reddy heater model r 50.. It ran for an hour, then shut off, I f I

Question

I have a reddy heater model r 50.. It ran for an hour, then shut off, I f I reset it, runs for 15 min or so shuts off... its old and borrowed, I think i might have a thermostat on it and just shuts off when it comes to temp... two k***s on the back side one red one white.. are either of these a thermostat?