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PsyRhoAirFnPbTdbW: RhoAir (Density of Air) is calculated <= 0

Hello,

I have read through the other posts that are related to this error and am still unable to fix my error. I am brand new to OpenStudio, so I am unsure of how to continue with my simulation. I'm working on the severe errors before I work through the warning errors. The only error I am receiving is below.

* Severe * PsyRhoAirFnPbTdbW: RhoAir (Density of Air) is calculated <= 0 [-0.52081]. * ~~~ * pb =[98088.00], tdb=[-914.65], w=[1.4285632E-002]. * ~~~ * Routine=CorrectZoneHumRat During Warmup, Environment=EAU_CLAIRE ANN CLG .4% CONDNS DB=>MWB, at Simulation time=07/21 00:00 - 01:00

I have natural gas fired furnaces with exhaust fans for each thermal zone, I do not have the furnaces autosized. They are 80% efficiency at 80,000 btu/h. I am just trying to establish a baseline for a small office before working with higher efficiency equipment. When running my simulation I currently have the OS measure surface matching and Energy+ measure add output diagnostics. Am I missing anything to just run a basic energy evaluation on a building?

I'm new so I cannot upload documents as of yet. I can send the error document and photo if needed. Thank you in advance.

Evan

PsyRhoAirFnPbTdbW: RhoAir (Density of Air) is calculated <= 0

Hello,

I have read through the other posts that are related to this error and am still unable to fix my error. I am brand new to OpenStudio, so I am unsure of how to continue with my simulation. I'm working on the severe errors before I work through the warning errors. The only error I am receiving is below.

* Severe * PsyRhoAirFnPbTdbW: RhoAir (Density of Air) is calculated <= 0 [-0.52081]. * ~~~ * pb =[98088.00], tdb=[-914.65], w=[1.4285632E-002]. * ~~~ * Routine=CorrectZoneHumRat During Warmup, Environment=EAU_CLAIRE ANN CLG .4% CONDNS DB=>MWB, at Simulation time=07/21 00:00 - 01:00

I have natural gas fired furnaces with exhaust fans for each thermal zone, I do not have the furnaces autosized. They are 80% efficiency at 80,000 btu/h. I am just trying to establish a baseline for a small office before working with higher efficiency equipment. When running my simulation I currently have the OS measure surface matching and Energy+ measure add output diagnostics. Am I missing anything to just run a basic energy evaluation on a building?

I'm new so I cannot upload documents as of yet. I can send the error document and photo if needed. Thank you in advance.

Evan