[EnergyPlus_Support] convergence problems...reasonable or not...and other Qs

["Jean marais" <jeannieboef@xxxxxxxxx>]

As people start streaming into my building in the morning, I get a convergence problem.

 ** Warning ** Inside surface heat balance did not converge with Max Temp Difference [C] =2.301E-003 vs Max Allowed Temp Diff [C] =2.000E-003
   **   ~~~   **  During Sizing, Environment=SUMMER DESIGN DAY IN KITA, at Simulation time=04/01 06:40 - 06:45
   ** Warning ** Inside surface heat balance did not converge with Max Temp Difference [C] =2.563E-003 vs Max Allowed Temp Diff [C] =2.000E-003
   **   ~~~   **  During Sizing, Environment=SUMMER DESIGN DAY IN KITA, at Simulation time=04/01 06:50 - 07:00
.
.
.
.
continues until...
.
.

===== Recurring Error Summary =====
   ************* The following recurring error messages occurred.
   *************
   *************  ** Warning ** Inside surface heat balance convergence problem continues
   *************  **   ~~~   **   This error occurred 14946 total times;
   *************  **   ~~~   **   during Warmup 0 times;
   *************  **   ~~~   **   during Sizing 12 times.
   *************  **   ~~~   **   Max=4.177895E-002 [C]  Min=1.986578E-003 [C]


1)Does this seem reasonable? A representative zone reports a infiltration ACH of about 0.4 (which I think is fair) and has the absolute minimum ODA made up by the mechanical ventilation. However to bring the required heating the mechanical system delivers about 0.5 ACH. 

Convergence problems, and setpoint not met problems are in the mornings when the stable surfaces (and persons) are suddenly exposed to more cold ODA in winter (Outdoor Dry Bulb 0-6 degC). My door schedule is as follows (set up in DesignBuilder):
- operation
	- Area door opens 80%
	- Time door is open 5%
	- Operation Schedule: OccupationSchedule

2)How does one decide on a door operation schedule?

How intelligent is the door operation in e+...does it notice changes in occupation numbers and assume higher operational frequencies? I think not (5%). I think that kind of logic is towards EMS. I think the amount of accuracy that would bring is not worth the effort and no one does that.

4)The building has Time Setpoint Not Met:

During Heating [hr] 2384.83 		
During Cooling [hr] 661.33	
During Occupied Heating [hr] 212.00	
During Occupied Cooling [hr] 661.33
 	
This seems to indicate a problem. I have specified sizing parameters of 1.25 and 1.15 for heating and cooling as per ASHRAE 90.1. What should I do to a) find the problem OR b) reduce the Time Setpoint Not Met hours? (this is a baseline case model)







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