simplest HVAC system
I want to build a simplest hvac system in energy plus with constant air temperature and constant air flow rate. Is it possible? Can I use ZoneHVAC:IdealLoadsAirSystem to build it?
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I want to build a simplest hvac system in energy plus with constant air temperature and constant air flow rate. Is it possible? Can I use ZoneHVAC:IdealLoadsAirSystem to build it?
Your best bet would probably be ZoneHVAC:PackagedTerminalAirConditioner with a Fan:OnOff. You can use this system to provide a set flow rate and temperature for cooling and heating operation, and it will cycle on and off to meet the load in the zone.
This is more complex than ZoneHVAC:IdealLoadsAirSystem because it requires fan, heating coil, cooling coil, and outdoor air mixing objects. I suggest looking at an example file to see how this object is used if you aren't familiar yet with how it works with the other objects.
Thanks. I'm looking into the example file. I also have another question. I want to change the initial condition of the simulation. (like the indoor temperature at the very beginning) But I found this from the documentation:
EnergyPlus “runs” the first day of the environment (starting with a set of hard-coded initial conditions) until the loads/temperature convergence tolerance values are satisfied or until it reaches “maximum number of warmup days.
Does it mean there is no chance I can modify the initial condition?
@vibra this is an excellent question! You should post it as a new question so that other people with the same question can find it too.
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Asked: 2015-03-08 13:25:22 -0600
Seen: 290 times
Last updated: Mar 09 '15
ZoneHVAC:IdealLoadsAirSystem is the simplest HVAC system in EnergyPlus. The next simplest might be the ZoneHVAC:PackagedTerminalAirConditioner. Are you looking for a central air system that serves several zones? If the system supplies constant air volume and constant temperature, how are the temperatures of the zone controlled to a set-point? Do you need reheat coils as well?
Thank you for your reply, Neal. This is my idea: when temperature is greater than 24C, Cooling start with constant T (15C) and constant flow rate. When temperature is lower than 20C, Heating start with constant T (27C) and constant flow rate.
I'm using energy+ for parameter optimization. So I hope the HVAC model could be as simple as possible.
So you want a system that cycles on and off to meet the zone setpoint? Why is it important that the airflow rate and temperature are constant?
Yes.I'm trying to identify the building as a black box. The HVAC system could be considered as input to the system. I need to know what exactly the value of the input is.