OA-FROM-SYSTEM

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Hi everyone,

When the outside air comes from the same system, I have to choose the system
in OA-FROM-SYSTEM or I leave ?undefined??

This cause an enormous change in my space heat performances and I couldn?t
identify the reason.

Thank you

Rodrigo Cerqueira

Rodrigo Cerqueira's picture
Joined: 2012-11-12
Reputation: 0

Hi Rodrigo,

As a general rule, do not feel compelled to use every input available. It is perfectly normal for many inputs to not apply for a given project - what's appropriate is ultimately a decision the modeler has to make for his/her own model. A balanced approach is to learn about/review and make a conscious decision to use or not use a specific inputs as they come up.

OA-FROM-SYSTEM specifically causes ventilation OA quantities for the child zones to be conditioned/dehumidified by another system. Right-click that field and read the corresponding help entries for more information. It is useful for specific system scenarios and approximations, but does not apply to every building. Many discussions regarding OA-FROM-SYSTEM are available for further reading in the mailing list archives, if needed.

Hope that helps!

~Nick
[cid:489575314 at 22072009-0ABB]

NICK CATON, P.E.

Nick-Caton's picture
Offline
Joined: 2011-09-30
Reputation: 805

Thank you Nick!

I choose to leave ? undefined ?The results are more consistent.

The problem is with that choice, my heating gas consumption increase greatly
and the values seem unreal.

I have read the discussion below but it not solve my problem. I know that
are many factor that could cause this but maybe anyone has experienced this
in the past.

http://lists.onebuilding.org/htdig.cgi/equest-users-onebuilding.org/2010-May
/004610.html

Any thoughts?

De : Nick Caton [mailto:ncaton at smithboucher.com]
Envoy? : 25 septembre 2012 14:38
? : Rodrigo Cerqueira; equest-users at lists.onebuilding.org
Objet : RE: [Equest-users] OA-FROM-SYSTEM

Hi Rodrigo,

As a general rule, do not feel compelled to use every input available. It
is perfectly normal for many inputs to not apply for a given project ?
what?s appropriate is ultimately a decision the modeler has to make for
his/her own model. A balanced approach is to learn about/review and make a
conscious decision to use or not use a specific inputs as they come up.

OA-FROM-SYSTEM specifically causes ventilation OA quantities for the child
zones to be conditioned/dehumidified by another system. Right-click that
field and read the corresponding help entries for more information. It is
useful for specific system scenarios and approximations, but does not apply
to every building. Many discussions regarding OA-FROM-SYSTEM are available
for further reading in the mailing list archives, if needed.

Hope that helps!

~Nick

cid:489575314 at 22072009-0ABB

NICK CATON, P.E.

Rodrigo Cerqueira's picture
Joined: 2012-11-12
Reputation: 0