Morning Warmup is a scheduled preconditioning operation that activates heating or cooling equipment before scheduled occupancy to bring building spaces from setback temperatures to comfort setpoints. This function ensures comfortable conditions immediately upon occupant arrival rather than requiring gradual temperature adjustment throughout the morning.
Timing and Duration
Morning Warmup duration depends on thermal mass, insulation quality, outdoor temperature, and equipment capacity. Typical commercial buildings require 30 minutes to 2 hours to raise temperature 5-15°F. Controllers can adjust startup timing automatically using historical data or manually using fixed schedules. ASHRAE guidelines recommend completing warmup 15 minutes before occupancy begins to ensure optimal conditions.
Energy Efficiency Considerations
Efficient Morning Warmup uses only necessary equipment capacity, avoiding full-capacity operation that triggers excessive energy demand. Two-stage heating systems operate in low stage initially, then increase capacity as temperatures approach setpoint. Combined with Optimal Start algorithms, Morning Warmup can deliver comfort while maintaining 5-10% energy savings versus continuous operation. Modern systems balance comfort expectations with energy cost, preventing unnecessary early-morning operation during mild weather conditions.