Baseboard heater thermostat issue
I have a marley heater 4 foot. On the heater is a double pole thermostat. There's 2 black wires and 2 red wires. 1 of the black wires reads cycle, the other black wire reads off. 1 of the red wires reads l1 and the other red wire reads l2. The power source coming to the heater is 2 black wires @ 220v from the panel. The heater either stays on all the time or f I change the wiring around it blows the breaker. Any help would be appreciated and respected. Thank you, rick