[Equest-users] Minimum Fresh Air AHU

[Andy Harrison]

Hi Omar,

If the heat reclaim is on a separate central air handler, with the cooling duty for each space on a local unit this avoids duplicating heat reclaim plant, reduces fan work by only circulating most of the cooling air locally, and allows each of the local units to be controlled separately to respond to variations in load (VAV vs Cooling terminals + min. fresh air).

Regards, Andrew

________________________________
From: Omar Katanani [omar at ecoconsulting.net]
Sent: 03 November 2010 22:38
To: Carol Gardner; Andy Harrison
Cc: equest-users at lists.onebuilding.org
Subject: RE: [Equest-users] Minimum Fresh Air AHU


Hi Guys,

May I ask why are you doing this process?

My understanding is that I double click on each zone, go to the Air flow/Outside Air, and enter the CFM of the fresh outside air. In what cases do I need to create an AHU for fresh air?

Thanks!
Omar

___________________________

Omar Katanani
Sustainable Design Engineer
Email: omar at ecoconsulting.net


EcoConsulting (Lebanon)
Nahas Building, 4th floor
4 St-Maron Street / Georges Haddad Avenue
Postal Code: 2028 5806 SAIFI
Beirut, Lebanon
Tel:       +961 (0) 1 971 266
Mobile:    +961 (0) 3 045 045


EcoConsulting (UK) Ltd
28 Marshalsea Road
London, SE1 1HF
Tel: +44 (0)207 939 0989
Fax: +44 (0)207 939 0981
Website: www.ecoconsulting.net



-----Original Message-----
From: equest-users-bounces at lists.onebuilding.org on behalf of Carol Gardner
Sent: Wed 11/3/2010 6:41 PM
To: Andy Harrison
Cc: equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] Minimum Fresh Air AHU

Andrew,

Create a Dummy space, very small 1ft x 1ft x 1ft with no load and then a
Dummy Zone for it and use this for your zone. I would not use Multi Zone but
rather PSZ if you are supply the fresh air at a constant volume or PVAVS if
it is supplied at a variable volume.

Best,

Carol

On Wed, Nov 3, 2010 at 2:48 AM, Andy Harrison <Andy.Harrison at arup.com>wrote:

> Hi All,
>
> I am trying to model a building which has a minimum fresh air AHU serving
> all zones, each of which also has a local cooling unit.  I was trying to
> model this using a single zone AHU for each zone, with outside air to all
> units coming from the multizone unit, which I created later, however I am
> getting an error saying that the multizone AHU needs to be assigned at least
> one zone.  How can I do this, when all of the zones are assigned to a local
> unit?  If I assign a small zone to get rid of the error, will the multizone
> AHU only be sized for the cooling load associated with this zone?  How can I
> confirm that the multizone AHU is sized for the appropriate fresh air load?
>
> Regards,
>
> Andrew
> ____________________________________________________________
> Electronic mail messages entering and leaving Arup  business
> systems are scanned for acceptability of content and viruses
>
> _______________________________________________
> Equest-users mailing list
> http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
> To unsubscribe from this mailing list send  a blank message to
> EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG
>



--
Carol Gardner PE