[Equest-users] PIU system central heat coil ouput

[David Reddy]

Hi Erik,
Yes, I should have mentioned that I tried that too.  That is typically 
what I do, but I thought perhaps defining a heat source with a small 
amount of capacity would be a reasonable way to alleviate the "free" 
heat energy I appear to be getting...

Attached is a quick and dirty wizard model that illustrates the issue 
(you will need to download .bin file or change to something 
comparable).  This is representative of the configuration I was going 
for except air-cooled DX.
David

On 10/17/2014 2:00 PM, Erik Kolderup wrote:
> David,
>
> Have you tried setting the HEAT-SET-T (Hot Deck Max Leaving Temp) to 
> no value (i.e. Restore Default)?  I think that any value for that 
> keyword enables heating at the AHU level.
>
> -Erik
>
> *Erik Kolderup, PE, LEED AP*
> erik at kolderupconsulting.com <mailto:erik at kolderupconsulting.com>| 
> 415.531.5198 | www.kolderupconsulting.com 
> <http://www.kolderupconsulting.com>
>
> On Fri, Oct 17, 2014 at 1:29 PM, David Reddy <david at 360-analytics.com 
> <mailto:david at 360-analytics.com>> wrote:
>
>     Hi all,
>     I am modeling a PIU system w/ a water-cooled DX coil and series
>     electric FPBs; no central or preheat heating coils.  Using eQ v3.64
>
>     SV-A report indicates heating capacity for system is 0.
>
>     Despite this configuration, hourly reports of for SYSTEM, 'Total
>     central heat coil output (Btu/hr)' indicates there is varying
>     amount of central heat energy output in the first 1-2 and in some
>     cases, the last 2-3 hours of many days in heating months (location
>     Seattle, WA).  This is also confirmed by looking at the difference
>     in energy reported between SS-A Heating and SS-B Zone Heating.  It
>     is not necessarily a trivial amount of energy, ~25% of total.
>
>     Have others observed this before, and if so, found a way to fix this?
>
>     Can't say I've tried everything I can think of, but this is what I
>     have tried:
>
>     A) Set HEAT-SOURCE = "ELECTRIC" and use a very small capacity both
>     -1 or -1000
>     B) A + setting HEAT-CONTROL = "CONSTANT"
>     C) B + set HEAT-SET-T various values, including minimum (50F)
>     D) Setting HEATING-SCHEDULE to something that locks out heating. 
>     This works, but also locks out zone heating, so not a viable solution
>
>     Thanks in advance for any input.
>     -David
>
>
>     -- 
>
>     David Reddy
>
>     *360 Analytics*
>     Building Energy Analysis Consultants
>     mail:     9750 3rd Ave NE, Suite 405, Seattle, WA 98115
>     office: 206.557.4732 x 201 <tel:206.557.4732%20x%20201>
>     cell: 206.406.9856 <tel:206.406.9856>
>     web: www.360-Analytics.com <http://www.360-Analytics.com>
>
>     _______________________________________________
>     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
>     <mailto:EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG>
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20141017/a3f5efe4/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: PIU Test.zip
Type: application/x-zip-compressed
Size: 7520 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20141017/a3f5efe4/attachment-0001.bin>