Within the limitations of the building systems, Federal agencies must—

(a) Operate heating and cooling systems in the most overall energy efficient and economical manner;

(b) Maintain temperatures to maximize customer satisfaction by conforming to local commercial equivalent temperature levels and operating practices;

(c) Set heating temperatures no higher than 55 degrees Fahrenheit during non-working hours;

(d) Not provide air-conditioning during non-working hours, except as necessary to return space temperatures to a suitable level for the beginning of working hours;

(e) Not permit reheating, humidification and simultaneous heating and cooling; and

(f) Operate building systems as necessary during extreme weather conditions to protect the physical condition of the building.