I have attached what I came up with
A room must be maintained between 20 and 30 degrees C using a combination of an AC and Heater, four thermostat: T20, T22 ,T28 and T30. If the temperature reaches 30 C, which activates T30. the AC must be energized and kept until the temperature decreases to 28C which deactivates T28. If the temperature reaches 20C which deactivates T20, the heater must be energized and kept energized until the temperature increases to 22C which activates T22. A master switch must be turned on for both the AC and heater to operate. Use latch and Unlatch instructions, Assign sequential addresses to the input and output starting from bit 0
A room must be maintained between 20 and 30 degrees C using a combination of an AC and Heater, four thermostat: T20, T22 ,T28 and T30. If the temperature reaches 30 C, which activates T30. the AC must be energized and kept until the temperature decreases to 28C which deactivates T28. If the temperature reaches 20C which deactivates T20, the heater must be energized and kept energized until the temperature increases to 22C which activates T22. A master switch must be turned on for both the AC and heater to operate. Use latch and Unlatch instructions, Assign sequential addresses to the input and output starting from bit 0