Gabi.ms's profile - activity

Yes, I tried @Julien Marrec. It doesn't simulate, a fatal error appears :/

" * Severe * GetZoneEquipmentData1: ZoneHVAC:EquipmentList = ZONE EQUIPMENT * ~~~ * ...multiple assignments for Zone Equipment Cooling Sequence=1, must be 1-1 correspondence between sequence assignments and number of equipments."

@Julien Marrec I did not know that, I'm sorry! Maybe I skipped that part when I was reading the rules. I'll remember from now on.

Again I'm here with some doubts. I want to model a real building (in E+), simulate a green roof on it and see the amount of kWh that I can reduce in my consumption. The problem is: I have a lot of zones (each zone is a room or a piece of a room) and in some of them I have like 20 Split ACs. I tried to model the zones with more than one AC (I used an Window AC to test it) but I always have to say that they are staged...when they actually aren't, so....

1. Is there a way to model the same type of equipment inside the same zone but working at the same time, not staged?
2. If there is not and I need to model as one HUGE AC, how can I do it? Can I still evaluate the kWh when I do this?

@Archmage, sorry for disturbing you again, but do you know why I keep getting the error even after I relaxed the Convergence Tolerance and sized the equipments?

Hi @Archmage! That was useful :) So...if I don't autosize anything inside my HVAC system, I can make them work together? Or would I need to use EMS?

I tried sizing everything (besides Outdoor Air Flow) and I keep getting that error...

I was trying to simulate in E+ two Window AC Units in the same Thermal Zone when I got this Warning in my Error File.

" * Warning * ZoneHVAC:WindowAirConditioner="WINDAC2" -- Exceeded max iterations while adjusting compressor sensible runtime to meet the zone load within the cooling convergence tolerance. * ~~~ * Iterations=50 During Warmup, Environment=SAO_PAULO/CONGONHAS ANN CLG .4% CONDNS DB=>MWB, at Simulation time=02/21 08:00 - 08:10"

What does that mean? When I simulated with only one Window AC it did not appear. I already tried changing the Convergence Limit to 70, but the error keeps appearing, so I think that's not the problem...

Can anyone help me?

Here is the link:IDF with only 1 AC and here is the link:IDF with 2 ACs

Yeah, sure! What I mean with this is that I have a lot of these equipment inside the rooms: http://www.lojasmm.com/Imagens/produt... (of course the outside part is outside the building). But they are not connected with each other at all, all of them work separately, besides the electrical control - they are switched on and off at the same time.

Yeah, it is kind the same problem, but...the solutions won't do for what I want, right?

I can't model them as just one, as the main objective of my project is how much less energy they will consume, and modeling as only a big one would distort the results, right? (No equipment would have that power) And my zones are already separated per room, so...I don't think I can split them even more...

Is that a dead end to me?

Should I try to model them as a central AC? With the average efficiency of the split ACs?

Hello everybody!

I'm new to all this energy modeling thing and I'm having a hard time trying to model my HVAC system :/ The model is for my project in University and it is from a real building, where I'm going to study the economic benefits of implementing a green roof.

The problem is: the building is full of Split Air-Systems!

I already know that to model that in E+ I need:

• HVACTemplate: Thermostat
• HVACTemplate:System:Unitary
• HVACTemplate:Zone:Unitary

But...there is more than one Split AC in each zone, and I can't figure it out how to reference that single zone in multiple systems - I keep getting errors about that.

Is there a way to have more than one AC in a single zone?

Thanks!

Hi everyone, I'm new to all this building energy modeling thing and I've got some doubts while creating my model. I'm modeling a real building and my objective is to simulate a green roof on it and evaluate if this modification can reduce the total eletric consumption (decreasing the use of the ACs).

I thought I should use the FullInteriorlandExterior option, and for that I created all my spaces with a convex geometry. But, many rooms got split up in many pieces, so I assigned Air Walls for the 'openings'. I've read that it transforms it into a Drywall material, so the heat is transfered, but not airflow. So I thought of using the "ZoneCrossMixing" to allow that.

My questions are:

1. Should I really use the ZoneCrossMixing and Air Walls to represent this openings? That way I would let them be two different thermal zones.

2. Should I merge the two spaces into one thermal zone? I was really afraid of all the possible problems of using Internal Mass.

3. Is there really a huge difference in results between FullExterior and FullInteriorandExterior? Should I forget all of the above and just use FullExterior?

I'm sorry for all these subjective questions, I have just come to a dead-end, so I thought I could use an expert advice :)

P.S: before anyone questions, this simulation is part of my thesis, but I really wanted to make it as precise as possible, since the building being simulated is from the company I am currently an Intern in ;D