[Equest-users] DHW Process Flow

[Tom Butler]

Lars, 

 

I still haven't run this to see the results, but the gist of the
responses I received is this;  First determine the daily usage per
person for dorms or per unit for apartments. Multiply that by the number
of residents/units, then divide by the number of minutes in a day to get
the GPM value. The other key is that the fractional schedule should then
be set up so that all of its values add up to 1.0. My methodology missed
the boat on both of these. 

All of the usage values can be found in the APSE manual, which also has
a method for accounting for  low-flow fixtures that I need to look into
since it can be factored into EAc1 calcs. 

Here is a good paper on fractional schedules for residential occupancy.
http://www.fsec.ucf.edu/en/publications/pdf/FSEC-RR-56-04.pdf

 

tb

 

 

 

From: Lars Fetzek [mailto:lfetzek at phoenixeng.us] 
Sent: Tuesday, September 15, 2009 3:32 PM
To: Tom Butler; equest-users at lists.onebuilding.org
Subject: RE: [Equest-users] DHW Process Flow

 

Tom and eQuesters,

 

    Did anyone answer your question?  I'll need to know this conversion,
too, for my project.

 

Lars Fetzek, EI

Phoenix Engineering Group

Tampa, Florida

 

________________________________

From: equest-users-bounces at lists.onebuilding.org
[mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Tom
Butler
Sent: Wednesday, August 19, 2009 3:14 PM
To: equest-users at lists.onebuilding.org
Subject: [Equest-users] DHW Process Flow

I am modeling a dormitory for EAc1 in version 3.60. I've calculated the
peak DHW load by using the flow rate of all of the fixtures on the hot
water loop (410 gpm). I have a schedule that accounts for the vacant
periods during the breaks and reduced usage in the summer when the
building is partially occupied. When I use the 410 gpm rate as the
process flow the energy consumption for hot water is astronomically
high. 

 

What fact do I need to apply to the calculated flow rate to get
realistic results?

 

Thanks

Tom Butler, LEED(r) AP
Direct Phone 404-253-1435 | Direct Fax 404-253-1335 

LORD, AECK & SARGENT ARCHITECTURE
Responsive Design * Technological Expertise * Exceptional Service 

 

www.lordaecksargent.com

 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20090916/662e9e04/attachment-0002.htm>