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Dewpoint control with EMS

I'm modeling a supermarket which controls dehumidification based on dewpoint (so casework does not have condensation). My strategy involves:

  • Create schedules for dewpoint setpoint AND relative humidity (RH) setpoint
  • control HVAC for the relative humidity setpoint
  • Use an EMS script to derive the RH needed to achieve the desired dewpoint, based on the zone temperature, then overwrite the relative humidity setpoint schedule. (The dewpoint calc is messy, so I made an equivalent curve formula)

Question: At what point should the ProgramCallingManager run the dewpoint calculation? Currently, I'm using "InsideHVACSystemIterationLoop" and it seems to work well, but I'm not familiar with the calling points described in the I/O Reference enough to be confident...

Dewpoint control with EMS

I'm modeling a supermarket which controls dehumidification based on dewpoint (so casework does not have condensation). My strategy involves:

  • Create schedules for dewpoint setpoint AND relative humidity (RH) setpoint
  • control HVAC for the relative humidity setpoint
  • Use an EMS script to derive the RH needed to achieve the desired dewpoint, based on the zone temperature, then overwrite the relative humidity setpoint schedule. (The dewpoint calc is messy, so I made an equivalent curve formula)

Question: At what point should the ProgramCallingManager run the dewpoint calculation? Currently, I'm using "InsideHVACSystemIterationLoop" and it seems to work well, but I'm not familiar with the calling points described in the I/O Reference enough to be confident...