Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
From the data shown, it appears that the evaporative cooler is overcooling the space, and the baseboard heat is coming on to maintain the zone heating setpoint. In the ZoneHVAC:EquipmentList set the heating and cooling sequence numbers so that the baseboard heat is first (1) and the evaporative cooling is second (2). This way the baseboard will only run if there is a heating load, regardless of what the evap cooler does. You may want to review the evap cooler controls if the space gets too cold.
| | 2 | No.2 Revision |
From the data shown, it appears that the evaporative cooler is overcooling the space, and the baseboard heat is coming on to maintain the zone heating setpoint. In the ZoneHVAC:EquipmentList set the heating and cooling sequence numbers so that the baseboard heat is first (1) and the evaporative cooling is second (2). This way the baseboard will only run if there is a heating load, regardless of what the evap cooler does. You may want to review the evap cooler controls if the space gets too cold.
Additonal details
When ZoneHVAC:EvaporativeCoolerUnit control type is ZoneCoolingLoadOnOffCycling, the unit is fully on for a timestep any time there is a cooling load, no matter how small. This can lead to significant overcooling during offpeak times. Until better controls are implemented via #6707 use several smaller units with SequentialLoad operation in the ZoneHVAC:EquipmentList. This will stage the units sequentially as needed.
