Standard 62.1 Secondary Recirculation VRP Calculation Errors

[EnergyArchmage]

Issue overview

Users doing detailed engineering checks reported problems with Standard 62.1 Ventilation Rate Procedure results. Found mistakes in code, one copy paste error for term Fb and a term missing in an equation for calculating zone Evz.

Fb should equal Ep

We see Fb values for cooling design match Ep values for heating design. Code inspection shows FbByZoneCool variable used where it should be FbByZoneHeat

User reports Evz values are coming out too high and sometimes even negative, code inspection finds missing the Ep term in missing in the equations for zone Evz.

To low Evz can cause systems to oversize when using VRP.

Details

Some additional details for this issue (if relevant):

• Platform (Windows, current develop)
• Version of EnergyPlus (if using an intermediate build, include SHA)
• Unmethours link or helpdesk ticket number

Checklist

Add to this list or remove from it as applicable. This is a simple templated set of guidelines.

• Defect file added (Fb_Evz_defectIDFs.zip)
• Ticket added to EnergyPlus Defect Complexity (Github Project)
• Pull request created (the pull request will have additional tasks related to reviewing changes that fix this defect)