Question-and-Answer Resource for the Building Energy Modeling Community
Get s tarted with the Help page
Ask Your Question

minimum humidity ratio equal to -1000 kgH2O/kgair [closed]

asked 2019-07-04 05:08:19 -0600

FSilenzi gravatar image

updated 2019-07-05 05:40:25 -0600

I have a very simple model, an air loop with an "OS:AirLoopHVAC:OutdoorAirSystem", an "OS:Coil:Heating:Electric", an "OS:SetpointManager:Scheduled", an "OS:Humidifier:Steam:Electric", an "OS:SetpointManager:Multizone:Humidity:Minimum", an "OS:Coil:Cooling:DX:SingleSpeed", an "OS:SetpointManager:Scheduled", an "OS:Air:Terminal:SingleDuct:ConstantVolume:NoReheat", a Thermal Zone with no equipment attached, and an "OS:Fan:ConstantVolume", like it is shown in the figure below. image description

This simple model is used to test the "OS:Coil:Cooling:DX:SingleSpeed" behavior, to check if the coefficients we calculated for the various curves of the coil model are correct. The preheat and the humidifier before the DX coil are needed to mimic the conditions of the external air since the weather file is used to reproduce the conditions of the exhaust air. This was needed because the real machine is working with the exhaust air as working fluid instead of using the outdoor air. In practice condenser and evaporator works with inverted temperatures. However, when I print the nodes minimum humidity conditions before and after the humidifier, I find this: image description

Does anyone have any clue about what is happening? FYI, in the weather file, the %RH is set at 30% (I used elements to edit it)

edit: added some informations

edit retag flag offensive reopen merge delete

Closed for the following reason the question is answered, right answer was accepted by FSilenzi
close date 2019-07-05 05:58:08.443867

1 Answer

Sort by ยป oldest newest most voted

answered 2019-07-05 05:57:49 -0600

FSilenzi gravatar image

I took the wrong variables, those are for Set point variables, not the actual variable value in the node. I checked the correct output and everything was as I expected.

edit flag offensive delete link more


Question Tools

1 follower


Asked: 2019-07-04 05:08:19 -0600

Seen: 99 times

Last updated: Jul 05 '19