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# lutinfr's profile - activity

2020-04-10 03:40:56 -0600 commented answer District cooling in IES-VE

Can you please give more detail. How to combine and import data into the ApHVAC chiller system ?

2019-01-06 21:47:04 -0600 answered a question E+ vs. IES: Loads Results comparison

You can change IESVE calculation methodology to ASHRAE to check so. As I know, CIBES is more on steady state methode, AS

2016-09-28 11:53:30 -0600 marked best answer Openstudio result viewer IP only, Is these a way to change result to SI ?

Openstudio result viewer IP only, Is these a way to change result to SI ? I'm using OpenStudio 1.8.5 with new "space" feature, exciting.

2016-05-24 03:22:09 -0600 commented answer Delete Subsurfaces without a Parent Surface

I have same issue and did not find the way to fix it.

2016-05-05 21:53:43 -0600 commented answer Water to Air heatpump curves - cooling mode

Thank you very much, I was missed understand between E+ and IESVE, they are completely different when modeling Water to Air Heatpump. Problem is now solved.

2016-04-27 04:53:32 -0600 asked a question Water to Air heatpump curves - cooling mode

In energyplus or OpenStudio, when editing Cooling performance curves of Waterto Air heatpump, there are only 5 coefficients for both "Total cooling" and "Cooling Power". Only Sensible Cooling has 6 coefficients. I know that all the curves are Bi-quadratic, then normally they have 6 coefficients. So the question is: How do I treat data when generating my own curve. Generate 6 coefficients then use 5, abandon constant value. Or tell excel to force constant to zero ?

Thank you.

2016-04-27 03:16:59 -0600 answered a question Double skin facade providing outside air to AHUs

I have not experienced this case in E+, I'm IESVE user. But I think the concept for getting this done is the same. As usual with double skin facade, I model cavity zones as thermal zones, separated them as individual thermal zone at each floor, cavities are connected vertically. In case I realize this for study, I separate them to 2 or even 4 at each floor to see roughly how the temperature gradient inside the cavity. Then using air net work on IESVE to connect them all and connect to AHU. Hope this can help.

2016-04-13 11:23:46 -0600 answered a question VAV works like CAV?

Fan should have flow control to manage how it’ll function, but current Openstudio does not provide enough flow control. You can try “Warmest Zone Supply Temp and Flow Reset” and set Strategy: FlowFirst – This is only flow control that I see in OS. Temperature control can be placed to other node.

2016-04-12 02:19:48 -0600 commented answer Simulation failed when building has a glassdoor

Hi Julien, I do not know how to mark the answer as accepted, can you point it out, thanks !

2016-04-12 02:14:25 -0600 commented answer Simulation failed when building has a glassdoor

Yes, thank you, we are very prudent with geometry

2016-04-11 20:57:54 -0600 answered a question VRF performance curve for non-flat low/high CapFT values

Here is the document about generating VRF performance curve:

Thank you Matthew, "applying to selected" works well for individual device, except VRF terminal. Terminals show in the thermal zones tab but will not show in HVAC system tab / VRF then generate error when simulation. For HVAC split, I wish it has "select all" tick at the top of thermal zones list.

2016-03-31 23:32:40 -0600 commented question Curiosity about Openstudio 2.0

Roger that ! Mr. MatthewSteen :) Thank you. Mr David.

New version of OpenStudio is planed to release on September so I would like to know that in the new version, is there any change or improvement on User Interface, especially on Sketchup plugin. And in Openstudio main application, when I have model that has many thermal zones, it has to drag & drop many times to VRF or to Airloop, it's boring task, I wish Openstudio 2.0 will have multiple selection for better drag & drop thermal zone to HVAC.

2015-10-04 21:22:07 -0600 commented answer Humidity control makes OS simulation fail

thanks a lot ! it works like a charm :)

2015-10-02 11:27:19 -0600 commented question Humidity control makes OS simulation fail

no one see this error when doing simulation ? :o

2015-09-29 21:38:04 -0600 marked best answer Simulation failed when building has a glassdoor

I have tested OS without using WWR scrip, simple building in image below. By default, from version 1.6 (may be wrong) OS set a rectangle that touch the bottom of each level as glassdoor and then simulation failed. Changing glass door to fix windows can fix this issue, E+ run fine. (I use VRF system in this case. OS 1.8.5) I think there are something wrong when OS translates glassdoor into E+.

### EDIT

Here is the eplusout.err

Program Version,EnergyPlus, Version 8.3.0-6d97d074ea, YMD=2015.09.15 16:36,IDD_Version 8.3.0
************* IDF Context for following error/warning message:
************* Note -- lines truncated at 300 characters, if necessary...
*************    785 FenestrationSurface:Detailed,
************* indicated Name=Sub Surface 1
************* Only last 3 lines before error line shown.....
*************    786   Sub Surface 1,                          !- Name
*************    787   GLASSDOOR,                              !- Surface Type
*************    788   ,                                       !- Construction Name
** Severe  ** IP: IDF line~788 Error detected in Object=FENESTRATIONSURFACE:DETAILED, name=SUB SURFACE 1
**   ~~~   ** Field [Construction Name] is required but was blank
** Warning ** IP: Note -- Some missing fields have been filled with defaults. See the audit output file for details.
** Severe  ** IP: Blank "required" fields found in input
** Severe  ** IP: Out of "range" values and/or blank required fields found in input
**  Fatal  ** IP: Errors occurred on processing IDF file. Preceding condition(s) cause termination.
...Summary of Errors that led to program termination:
..... Reference severe error count=3
..... Last severe error=IP: Out of "range" values and/or blank required fields found in input
************* Warning:  Node connection errors not checked - most system input has not been read (see previous warning).
************* Fatal error -- final processing.  Program exited before simulations began.  See previous error messages.
************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning; 0 Severe Errors.
************* EnergyPlus Sizing Error Summary. During Sizing: 0 Warning; 0 Severe Errors.
************* EnergyPlus Terminated--Fatal Error Detected. 1 Warning; 3 Severe Errors; Elapsed Time=00hr 00min  0.23sec

2015-09-29 01:55:41 -0600 asked a question ViewModel measure goes wrong when building orientation non-zero

When building orientation = 0

Then, put non zero

Result ! opps

hope fully this is only presentation in viewmodel that makes fault, not E+'s shading calculation error.

2015-09-28 23:44:51 -0600 edited question Humidity control makes OS simulation fail

When I put humidity control into HVAC air side network, any kind of humidity control makes simulation fail. And I tried to fix this problem, but still no way. Humidity setpoint does not show as an icon in the airloop network (fig 1), it simply disapered, but it's properties apper on the left pane - then simulation fail, there is no way to delete this setpoint control.

In case replacing humidity setpoint by a temperature setpoint (drop to the same node), I got both properties for temperature and humidity on the left, simulation fail too (fig 2)

Only way to fix this condition is to delete whole airside and rebuild, oh yes, rebuild :)