Chiller Refrigerant Migration free cooling

[rraustad]

Issue overview

Description: Chillers can provide free cooling when outdoor conditions are favorable. At outdoor temperatures lower than the evaporator fluid temperature set point, the refrigerant can naturally migrate from the evaporator back to the condenser without the use of the compressor. The act of refrigerant migration can provide up to 25% of the chiller rated capacity or more if condensing temperatures are lowered (https://p2infohouse.org/ref/25/24330.pdf). EnergyPlus does not currently have this capability.

Details

Some additional details for this issue (if relevant):

• Platform (Operating system, version)
• Version of EnergyPlus (if using an intermediate build, include SHA)
• Unmethours link or helpdesk ticket number

Checklist

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• Defect file added (list location of defect file here)
• Ticket added to Pivotal for defect (development team task)
• Pull request created (the pull request will have additional tasks related to reviewing changes that fix this defect)