How to turn off hot water loop and how to make a FCU+DOAS system simulation

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Hi all:
I am simulating a building which dosen't need heating via FCU,but in eQuest's air-side system,there is the 4-pipe Fan coils with HW heat. I don't need heating so how can i turn off the heat water loop in detailed interface mode?

Another question is HOw to service the whole building with both FCU and DOAS?

Thank you so much!
2010-04-17

tsea2005

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You can just select it as it is and then remove it in Detailed edit or set the heating level to something extremely low (55F).

John Grando LEED AP

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you can keep the heating and hot water in the model, and simply use "non
heating" thermostat schedules that will allow the space to be satisfied
without turning on the hot water coils. also in the hot water loop there is
a snap temperature. set this to 120 or something high and the boilers and
attached equipment will never turn on.

also for the DOAS system with FCU equipment. i have done exactly that and
gotten good results. Start by setting all your FCU systems to have
OA-FROM-SYSTEM to the DOAS system and make sure that the DOAS system is
attached to a "dummy space." this space doesn't need to have walls or
loads, just 1sqft of space and the correct thermostat schedules and it
should work just fine.

2010/4/19 Grando, John

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Rob Hudson

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Hi Rob Hudson,
First thanks for your reply. I followed you advice that set the snap temp to 120, and there is no heating load, I made it .
But for the DOAS system ,as you said that the dummy space doesn't need to have walls or loads,I created a new floor named dummy floor using a box with 1ft width ,1ft depth and 1ft floor-floor.Then in the dummy floor ,I created a child space named dummy space with box-shaped,1ft width ,1ft depth. After this ,I created a new HVAC system named DOAS system , that is SZRH.Here is the problem:the DOAS system's "control zone" dose't include the dummy space defined ealier,as the chart showed below, So I have to cancel.

2010-04-20

The simulation can't run ,then I checked the building description?it turned out as the chart showed below:

I do know that I have misunderstood the method definfying the dummy space ?what is the correct one?I?ve attached my INP and PD2 files.

2010-04-21

tsea2005

???? Rob Hudson
????? 2010-04-19 22:07:20
???? Grando, John
??? tsea2005; equest-users at lists.onebuilding.org
??? Re: [Equest-users] How to turn off hot water loop and how to make aFCU+DOAS system simulation

you can keep the heating and hot water in the model, and simply use "non heating" thermostat schedules that will allow the space to be satisfied without turning on the hot water coils. also in the hot water loop there is a snap temperature. set this to 120 or something high and the boilers and attached equipment will never turn on.

also for the DOAS system with FCU equipment. i have done exactly that and gotten good results. Start by setting all your FCU systems to have OA-FROM-SYSTEM to the DOAS system and make sure that the DOAS system is attached to a "dummy space." this space doesn't need to have walls or loads, just 1sqft of space and the correct thermostat schedules and it should work just fine.

2010/4/19 Grando, John

You can just select it as it is and then remove it in Detailed edit or set the heating level to something extremely low (55F).

John Grando LEED AP

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This is easy to fix. You cannot assign systems directly to spaces, they must be associated with a thermal zone. Under ?airside HVAC? right click on project and choose ?create thermal zone.? Assign the dummy zone to the dummy space and then assign the system to the zone (double click on the zone, under ?basic specifications? set the parent system to DOAS).

Kelsey Van Tassel

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