Description Input 115VAC 50/60 Hz, 0.48A. Output 24VAC/40VA (1.67A) output. Temperature Operating: 0° C to 49° C (32° F to 120° F). Storage: - 20° C to 70° C ( - 4° F to 158° F). Relative Humidity 85% +/- 5%. BTU/Hr. (approx.): 21 BTU/Hr. System AC input VA requirement: 55.2VA.