Modelling Non AC building in eQUEST

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Dear eQuesters,

I have the following doubt.

1. This is a hostel building. all the rooms are non ac except the wardens
cabin and the counselling room. These two rooms have split units.

2. I have to model this for thermal comfort compliance - so i need to show
that there are less unmet hours in the building.

How do I go about this?

What i thought was as under,

1. I made the entire model and assigned the ac and non ac spaces as per
design.
2. I plan to put a system in the non ac rooms, such that the CFM generated
due to ceiling fans can be put as Fan Flow Parametres. A 12 hour fan
schedule (as per the evening + night time occupancy hours) can be assigned
to this. Other than this there will be no input parameter assigned to this
system - no COP, no efficiency. Other than this these rooms have to behave
as non ac spaces.

Now my questions,
1. Do you think this is logical way to do?
2. Is there any other way to go about this?
3. If what i have described in point 2 is okay, while i assigning systems
what should it be? Like Sum or FNSYS or VAVS etc? Please let me know the
specifics

Please give me an insight into this ya.

Regards
Kirti

*Kirti Pabrekar - Patil*
M. Arch, LEED GA,
IGBC AP, GRIHA Trainer & Evaluator,

*Green is a commitment...not a competition*

via Equest-users's picture
Joined: 2016-07-15
Reputation: 400

Not sure how much help I would be but I did find this online tool that looked useful.

http://comfort.cbe.berkeley.edu/

And here?s another downloadable calculator for cool roofs/passive ventilation (Wow).

http://thermalcomfort.co.in/resources/calculators
Exploring cool-roof and passive ventilation techniques to achieve thermal comfort.

If you were working on this as part of a larger LEED cert, like LEED NC, you would usually end up having to model cooling systems in both models serving all conditioned zones whether or not your design incorporates a cooling system of any kind (because ASHRAE 90.1 Appendix G would dictate how to proceed in that case).

I?m sure others here would have more useful info for your specific case though.

Good luck with the model!

Chris Baker
CCI Alliance of Companies
Fort Wainwright, AK

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Joined: 2016-07-15
Reputation: 400

Hi Kirti,

My Comments are as follows within the mail.

---------- Forwarded message ----------
From: Kirti Pabrekar - Patil via Equest-users <
equest-users at lists.onebuilding.org>
To: "equest-users-request at lists.onebuilding.org" <
equest-users-request at lists.onebuilding.org>, "
equest-users at lists.onebuilding.org"
Cc:
Date: Tue, 14 Feb 2017 19:04:33 +0530
Subject: [Equest-users] Modelling Non AC building in eQUEST
Dear eQuesters,

I have the following doubt.

1. This is a hostel building. all the rooms are non ac except the wardens
cabin and the counselling room. These two rooms have split units.

[SK]: So you can have only these rooms to be conditioned.

2. I have to model this for thermal comfort compliance - so i need to show
that there are less unmet hours in the building.

[SK]: You can also provide the SS-O and SS-N reports for showing thermal
comfort conditions.

How do I go about this?

What i thought was as under,

1. I made the entire model and assigned the ac and non ac spaces as per
design.

2. I plan to put a system in the non ac rooms, such that the CFM generated
due to ceiling fans can be put as Fan Flow Parametres. A 12 hour fan
schedule (as per the evening + night time occupancy hours) can be assigned
to this. Other than this there will be no input parameter assigned to this
system - no COP, no efficiency. Other than this these rooms have to behave
as non ac spaces.

[SK]: To make any building non-ac you are required to have the FAN switched
off for 24 X 7 hours.
You are required to have OFF FAN schedule for the systems serving the
non-ac areas.
In this way you can have those areas as being served by not any HVAC fan or
then there is no HVAC there installed.
You can put any system and have the zone under it and then have all the
time HVAC Fan to be switched off.

Now my questions,
1. Do you think this is logical way to do?

2. Is there any other way to go about this?

3. If what i have described in point 2 is okay, while i assigning systems
what should it be? Like Sum or FNSYS or VAVS etc? Please let me know the
specifics

[SK]: I think this is the most simple way to do which i have suggested.

Please give me an insight into this ya.

Regards
Kirti

*Kirti Pabrekar - Patil*
M. Arch, LEED GA,
IGBC AP, GRIHA Trainer & Evaluator,

*Thanks,*
*Sharad.Kumar*

via Equest-users's picture
Joined: 2016-07-15
Reputation: 400

I have doubts about how you're doing this. I used to model
non-conditioned buildings in Asia by using the Residential (RESYS)
system and setting the Heating and Cooling Setpoint temperatures way
below or above the actual room temperature so that they never come on,
e.g., Heating at 99 and Cooand , which has a different VENT-TEMP-SCHEDULE

Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 205A
Moraga CA 94556
yjhuang at whiteboxtechnologies.com
http://weather.whiteboxtechnologies.com for simulation-ready weather data
http://www.whiteboxtechnologies.com
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"

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Joined: 2016-07-15
Reputation: 400

Sorry,
last message got sent out inadvertently while I was editing it. The full message is
contained below.

-------- Forwarded Message --------
Subject: Re: [Equest-users] Modelling Non AC building in eQUEST
Date: Fri, 17 Feb 2017 14:59:15 -0800
From: Joe Huang via Equest-users
Reply-To: Joe Huang
To: equest-users at lists.onebuilding.org

I have doubts about how you're doing this. I used to model non-conditioned buildings in
Asia by using the Residential (RESYS) system and setting the Heating and Cooling Setpoint
temperatures way below or above the actual room temperature so that they never come on,
e.g., Heating at 99 and Cooand , which uses a different VENT-TEMP-SCHEDULE for the
temperature above which windows are expected to open, e.g., 75 F, PROVIDED that the
outdoor air temperature or enthalpy is lower. To be doubly safe, you can set the Heating
and Cooling capacity to very small numbers, like 0.1, etc., although that's immaterial
because they would never come on.

I don't see how you can derive unmet hours for an unconditioned space, but you can derive
the hours above comfort, e.g., 78 F, and tabulate that. I used to call them Heating or
Cooling Discomfort Hours :-)

Joe

Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 205A
Moraga CA 94556
yjhuang at whiteboxtechnologies.com
http://weather.whiteboxtechnologies.com for simulation-ready weather data
http://www.whiteboxtechnologies.com
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"

via Equest-users's picture
Joined: 2016-07-15
Reputation: 400

Another sorry (boy, I'm turning into a sorry character...)

As pointed out by a friend, I made a mistake on the set-points. Heating
should be way low, like 30F and cooling be way high, like 99F, to keep
the fake system from turning on. My main point, though, is that you
need to model a system in order to allow for Natural Ventilation, or
otherwise you would be modeling a greenhouse that's liable to have very
high internal temperatures.

Joe

Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 205A
Moraga CA 94556t
http://weather.whiteboxtechnologies.com for simulation-ready weather data
http://www.whiteboxtechnologies.com
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"

via Equest-users's picture
Joined: 2016-07-15
Reputation: 400