To help others answer this question better, you should paste in the objects that appear in your expanded IDF (file ending in [name of your IDF].expidf). Since you are using the HVACTemplate:Zone:IdealLoadsAirSystem object, this will be expanded into one or multiple "standard" objects before running EnergyPlus.
Also, be careful about using the correct documentation. Your model is for v8.5, but the documentation "Source" link you provide is for v8.7. Here is the same outputs section for v8.5.
That relationship is only valid when the outdoor air is warmer and more humid than the zone air which only happens in the afternoons of Jul 14 and Aug 3 for this simulation with Copenhagen IWEC weather. The qualifier "When the economizer is not active . . . " should be expanded to "When the outdoor air and the supply air both require sensible and latent cooling these values are related by the following equation:" but that's rather confusing.
The reporting currently separates out the Outdoor Air Sensible/Latent Cooling/Heating values independently, and then adds them together for the totals. So this balance can get even more confusing when the outdoor air is warmer and drier than the zone. If anyone is interested in the exact algorithm, see the code here.
Z.I.L. "Heat Recovery" T. C. E.
Z.I.L. "Outdoor Air" T. C. E.
I'm still a bit confused about the meaning of the output "Outdoor Air"
1) how is it different from "Supply Air" and why isn't it contained in "Zone".?
2) Is the exhaust air being mixed or staying separate from the supply air (for instance through the heat exchanger/recovery) - concerning pollutants such as CO2?
Hello, I'm also having this issue and am still a little confused with the answer. With this equation from the reference: Zone Ideal Loads Supply Air Total Cooling Energy + Zone Ideal Loads Heat Recovery Total Cooling Energy = Zone Ideal Loads Zone Total Cooling Energy+ Zone Ideal Loads Outdoor Air Total Cooling Energy. For example an hour in January I will get the LS of the equation being larger than the RS and in that same hour the RS being larger than the LS. It says the total supply cooling is zero while the zone total is some number. In the cooling case, is that due to free cooling?
Most likely yes. Report the System Node temperatures and humidities to see what's happening to help understand.
Zone Ventilation Sensible/Latent HG/HLoss the sum of each component is not equal to the value calculated by eplus in Zone Total Ventilation HG/HL as per image attached. Has it some kind of concealed elements that is not clearly show up?
Each load type (sensible, latent, and total) is binned separately into the gain and loss columns. If the air is cool and moist, for example, it will be sensible loss and a latent gain. The total for that time step could land in either the gain or loss column. I personally don't find the the total gain/loss columns to be very useful, others do.
Hi @MJWitte, for the is clear the presence of both loads, actually I am wondering why the total variables are not equal to the sum of each element, in this case latent+sensible gain/loss ? Should I have to doubt even the other totals?
Perhaps an example will help.
what is Enable Ideal Air Loads?
lower u-value with higher cooling energy?