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2022-05-20 09:22:39 -0500	received badge	● Popular Question (source)
2015-08-27 22:19:17 -0500	commented answer	heating energy when changing cooling setpoint temperature Thank you very much, that helps a lot=)
2015-08-26 20:58:16 -0500	received badge	● Scholar (source)
2015-08-25 20:35:09 -0500	asked a question	heating energy when changing cooling setpoint temperature Hello, In my model, Standard VAV-Reheat created from HVACTemplate objects is used. The thermostat for heating is 20C, and the one for cooling varies from 20C to 26C. Anyone knows why heating load changes a lot when I only change cooling set point temperature? Theoretically, it should not be influenced. Maybe because of the Reheat? By the way, in Thermostat: DualSetpoint, is that possible that cooling set point and heating set point are the same? If not, what is the deltaT at least? Thanks =)
2015-08-24 02:36:05 -0500	commented answer	VAVTemplate-Maximum iterations exceeded yes. In my case, i used the EnergyPlus Expand IDF getting by HVACtemplate:VAV as my new idf. Firstly, i changed from Pump:ConstantSpeed to Pump:VariableSpeed, and Boiler Flow Mode in OBJECT Boiler:HotWater from ConstantFlow to LeavingSetpointModulated. Then setting the Central Cooling Design Supply Air Temperature and the one of heating the same. The warning were gone=)
2015-08-19 21:40:47 -0500	commented answer	VAVTemplate-Maximum iterations exceeded Thanks, i just did it =) All warnings were gone.
2015-08-17 01:49:02 -0500	commented answer	VAVTemplate-Maximum iterations exceeded thanks rraustad, I will try these two. Just one question, how can we set the cooling and heating supply air temperature? Is that in object "Sizing:System", Central Cooling/Heating Design Supply Air Temperature? Thanks again=)
2015-08-17 01:49:02 -0500	received badge	● Commentator
2015-08-13 01:10:27 -0500	received badge	● Editor (source)
2015-08-13 01:09:40 -0500	asked a question	VAVTemplate-Maximum iterations exceeded Hello, I got 2645615 Warnings which are same as link text when using HVAC template - ZoneVAVwatercooled for a large building . My question is that: Even if there are so many warnings, the system doesn't converge for only 07/27 09:30 - 09:40 and 08/18 11:20 - 11:30 and my timestep is 10 min. Could I ignore these warnings? If not, how can i fix this problem? Thanks=) More details: * Warning * SimHVAC: Maximum iterations (20) exceeded for all HVAC loops, at RUN PERIOD 1, 07/27 09:30 - 09:40 * ~~~ * The solution for one or more of the Air Loop HVAC systems did not appear to converge * ~~~ * Air System Named = VAV SYS1 did not converge for mass flow rate * ~~~ * Check values should be zero. Most Recent values listed first. * ~~~ * Demand-to-Supply interface mass flow rate check value iteration history trace: 65.536106,83.211257,23.244115,58.052126,90.984201,27.363113,65.536130,83.211285,23.244115,58.052126, * ~~~ * Supply-to-demand interface deck 1 mass flow rate check value iteration history trace: 0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000, * ~~~ * Air System Named = VAV SYS1 did not converge for temperature * ~~~ * Check values should be zero. Most Recent values listed first. * ~~~ * Demand-to-Supply interface temperature check value iteration history trace: 5.555677E-002,7.269640E-002,1.850951E-002,5.245884E-002,7.519209E-002,2.136337E-002,5.555679E-002,7.269643E-002,1.850951E-002,5.245884E-002, * ~~~ * Supply-to-demand interface deck 1 temperature check value iteration history trace: 1.241118,1.675333,0.419872,1.213315,1.669355,0.470383,1.241119,1.675334,0.419872,1.213315, * ~~~ * Air System Named = VAV SYS1 did not converge for energy * ~~~ * Check values should be zero. Most Recent values listed first. * ~~~ * Demand-to-Supply interface energy check value iteration history trace: 1713822.876912,2173451.995929,606978.653270,1516346.701414,2378253.912276,714557.723354,1713823.524251,2173452.732933,606978.656808,1516346.706538, * ~~~ * Supply-to-demand interface deck 1 energy check value iteration history trace: 666322.964022,-1039523.438037,250718.781313,653731.204601,-1052064.940010,283512.232175,666323.237488,-1039523.823601,250718.781425,653731.203318, * Warning * SimHVAC: Maximum iterations (20) exceeded for all HVAC loops, at RUN PERIOD 1, 08/18 11:20 - 11:30 * ~~~ * The solution for one or more of the Air Loop HVAC systems did not appear to converge * ~~~ * Air System Named = VAV SYS1 did not converge for mass flow rate * ~~~ * Check values should be zero. Most Recent values listed first. * ~~~ * Demand-to-Supply interface mass flow rate check value iteration history trace: 34.666404,34.205766,36.931524,37.392130,34.666596,34.205498,36.934014,37.384023,34.722262,34.125857, * ~~~ * Supply-to-demand interface deck 1 mass flow rate check value iteration history trace: 0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,0.000000, * ~~~ * Air System Named = VAV SYS1 did not converge for temperature * ~~~ * Check values should be zero. Most Recent values listed first. * ~~~ * Demand-to-Supply interface temperature check value iteration history trace: 2 ... (more)
2015-07-29 22:20:09 -0500	commented answer	zoning for large building Thanks David. Since my building envelope is downloaded from Sketchup Warehouse and I did not use the Space Diagram, this method may be not applicable to building zoning in my case. In addition, can we use zone multipliers if every story are a little different? Thanks again!
2015-07-29 21:26:08 -0500	commented question	zoning for large building @Lincoln In my model,every story is a little different, and it looks like a ladder platform ( floor area is larger than roof ceiling area). In this case, can i also use zone multipliers? Thanks!
2015-07-28 05:29:01 -0500	asked a question	zoning for large building Hi sorry I have another question of zoning a large building. To zone a large and irregular bulding(in my case, it's a 80-story building) into "perimeter and core zones", i found "automatics zones" in AutoDESK. But is that also possible in Openstudio ? If not, will we finally get idf file from AutoDESK? Thanks! Eva
2015-07-27 21:52:07 -0500	commented question	set surface construction hi thanks for this method. After exporting idf from Openstudio, constuctions in EnergyPlus are also changed.
2015-07-27 04:30:44 -0500	asked a question	set surface construction Hello, in my building model there are more than 600 surfaces of which about 300 are walls with same construction. Is there a effective method to set the construction all together instead of doing that one by one? Thanks =)
2015-07-26 21:10:15 -0500	commented answer	Set People and Lights for Internal Mass thanks very much=)
2015-07-24 02:19:52 -0500	received badge	● Supporter (source)
2015-07-24 00:54:46 -0500	commented answer	Set People and Lights for Internal Mass thanks David :)
2015-07-24 00:42:18 -0500	commented answer	Set People and Lights for Internal Mass yes we can do that, thanks rraustad! In addition you mentioned that internalMass for floors is not recommended , could you please tell me why? This would be very important for me, because I intended to use internalmass to simplify my model. Thanks again =)
2015-07-23 23:04:30 -0500	received badge	● Student (source)
2015-07-23 21:39:11 -0500	asked a question	Set People and Lights for Internal Mass Hi when the matched surfaces like floor and roof ceiling are translated into Internal Mass in EnergyPlus, how to deal with the internal load? I mean for light, equipment and people etc, ususally we set x watts per Zone Floor Area. But you know in this case, Internal Mass is not floor area anymore. Thanks!
2015-07-23 03:50:19 -0500	commented answer	Partition walls inside same zone Hi when the surfaces like floor and roof ceiling are translated into Internal Mass, how do you deal with the lighting setting? I mean for light, equipment and people etc, ususally we set x watts per Zone Floor Area. But you know in this case, Internal Mass is not floor area anymore. Thanks!
2015-07-23 01:31:00 -0500	commented question	invalid Outside Boundary Condition Object=<blank> oh got it, thanks :-)
2015-07-22 22:24:38 -0500	commented question	invalid Outside Boundary Condition Object=<blank> David, thanks very much. I just solved this probelm by doing surface matching in Openstudio. But I have another question: when i import idf from openstuio where a two floor building is built by creating space from diagram and surface matching is also done, it seems that the two matched surfaces are lost and there are only ten surfaces in EnergyPlus. Thank you again!
2015-07-22 09:22:27 -0500	asked a question	invalid Outside Boundary Condition Object=<blank> Hi, i have a problem about surface Outside Boundary Condition when i use energyplus and openstudio . the question is that: * Severe * BuildingSurface:Detailed="SURFACE 18", invalid Outside Boundary Condition Object=<blank>. * ~~~ * ..Outside Boundary Condition="Surface" must be non-blank. * ~~~ * ..This surface will become an adiabatic surface - no doors/windows allowed. In my case, there are two matched surfaces in two different spaces and two different thermal zones. So which Outside Boudary Condition should we choose, surface(which i chose and caused this error), or Adiabatic etc? In addition, if the two matched surfaces are in two different spaces but one same thermal zone, which Boundary Condition? Thanks!