Yes, this is a known problem. The sizing routines don’t know about the DOAS, nor how it will eventually operate. The easiest workaround is probably to use OtherEquipment to provide internal gains that account for the missing DOAS. Use the schedule day types so these loads only happen during design days. You’ll have to figure out the thermal load from the DOAS in Watts, using mass flow rate times specific heat of moist air times temperature difference between DOAS supply and zone air. For cooling use negative value for internal gain.
From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx]
Sent: Thursday, November 6, 2014 10:59 AM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: Re: [EnergyPlus_Support] Re: Two air systems serving one zone
Sorry. Let me reiterate. When I use two systems, energy plus cannot meet the load most likely because it didn't size them correctly. If with one system, auto size will work correctly and properly size it to meet the load.
HJ
On Nov 6, 2014, at 12:08, lmblanes@xxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:
HJ
Please could you clarify your question? Your last sentence is confusing.
Do you mean that you are not able to meet the load therefore you need to model two air systems?
Regards
Luis
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Posted by: "Brent Griffith" <Brent.Griffith@xxxxxxxxxxxxxxxxxx>
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