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No HVAC Energy Used in Simulation

asked 2017-03-08 16:44:02 -0500

updated 2017-03-18 20:37:26 -0500

EnergyPlus v8.5

System7-Boiler/Chiller-VAV. System will complete an auto sizing run. and generates an SVG diagram. No apparent error from system disconnects. System has Thermostats and Availability Managers assigned...and while equipment is sized, there is no HVAC energy. Lights and Plugs show up.....but No Fans, No Pumps, 0. Any ideas, b/c I'm buffaloed ? can send file...

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Did a Variable for AvailabileManager...its a 2 for all of the hours run. Compared this to another model which IS behaving...its also a 2....I think I've done and redone the availability managers and compared to the 5ZoneVAV E+ example....I'm still confused. Thanks in advance for any ideas....

dradair's avatar dradair  ( 2017-03-08 18:49:12 -0500 )edit

Maybe your building is really awesome?!

More seriously, do you get unmet hours? Send the file, hard to tell what's causing this...

AvailabilityManager:Scheduled having a value of 2 is good (see this)

Julien Marrec's avatar Julien Marrec  ( 2017-03-09 04:05:58 -0500 )edit

do you add cooling and heating setpoints in the space ?

BL's avatar BL  ( 2017-03-09 08:15:14 -0500 )edit

The building isn't anything special - so it better use some energy! There are a ton of unmet hours in the project. I have Thermostat:Setpoint:DualSetpoint and that is assigned in each of the ZoneControl:Thermostat ....I'll send the file to you @Julien Marrec and will be sure the solution is reported back because I am quite....confused.

dradair's avatar dradair  ( 2017-03-09 09:01:14 -0500 )edit

I guess DualSepoint should be used with plant loop, not air loop

BL's avatar BL  ( 2017-03-09 09:24:04 -0500 )edit

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answered 2017-03-18 20:38:54 -0500

Just answering so we can close the thread...

Seems like his issue was that the air loop was ill-formed, while it still passed the E+ integrity tests. Namely, the Outside Air Mixer was connected on the demand outlet node, instead of being connected to the supply inlet node.

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I know that because I got the file in private and spent a couple of hours hammering on every single point until I found the problem... This type of troubleshooting doesn't really belong on UnmetHours and I will no longer provide such services for free.

Julien Marrec's avatar Julien Marrec  ( 2017-03-18 20:39:17 -0500 )edit

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Asked: 2017-03-08 16:44:02 -0500

Seen: 384 times

Last updated: Mar 18 '17