Room & conditions
Ambient = design temp of the space surrounding the room (plant room / warehouse / outdoors). Ground temp is used for the floor ΔT.
Panel construction
—
Glass display doors optional
Door area is subtracted from panel wall area and the glass U-value applied instead — plus 65% of the frame / anti-sweat heater wattage entering the room. If you have display doors, also set door usage below to heavy or retail display.
Infiltration
Air changes are looked up from the standard volume table and scaled by the usage factor (reduced 30% for sub-zero rooms).
Product load
Sensible heat above/below freezing plus latent heat is included automatically when the product must cross its freezing point (e.g. fresh product into a freezer).
Internal loads
Sizing
Coolrooms are typically sized at 16 h run time, freezers at 18 h (defrost + reserve). Fan + defrost allowance covers evaporator fan motors and defrost heat re-entering the room.
Required refrigeration capacity
— kW
— BTU/hr · — kJ/day