All:
Does anyone know (or have a handy reference or documentation ) for explaining how eQUEST handles determination of distribution losses for Supply and Return ductwork described as located in un-conditioned plenum spaces....? I feel comfortable that I am understand eQUEST's input requirements clearly, but when I stop to think about it, I am unclear on how the sequential behavior of (LOADS) and (SYSTEM/PLANT) modules handle the dynamic interaction introduced when a change to the model of a) reducing duct leakage and/or b) insulating supply ductwork is introduced.
Along those lines - I'm unable to find any information in the 'standard'' output reports (using the D2SimViewer) to help me understand what is being reported for thermal conditions in an unconditioned plenum. Aside from creating custom hourly report variable for the zone temperature, does anyone have any other ideas for retrieving this information?
Finally - it's been my experience, from poking my head above plenty of ceiling tiles to confirm as-built drawings, that shooting a thermal image or two reveals that many commercial building HVAC systems do have supply and return ductwork distribution systems that would benefit from repair of insulation, addition of mastic, and in some cases, reconnection! In many cases, a cheap fix, whose savings can help pay for other more costly improvements.
Has anyone else who has modeled similar improvements to ductwork systems located in un-conditioned areas experienced unexpected results?
All the Best,
_Chris
Chris Balbach, PE, CEM, BEMP, CMVP, BESA, BEAP
hi,
I'm simulating CHW Plant with CAV AHU's and bunch of packaged/split system units around supporting areas of the hospital/clinic.
I get the warning messages similar to below for almost all my zones and my gas heating hot water is extremely low, no matter what I try do on the heating side. I added baseboards but it didn't make a difference-still have bunch of zones underheated looking at the ss-o's.
Do you any other hints you can share where else to look for the HHW low consumption?
Best,
Nikola
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I would first check your system level inputs. Have you used a VAV system?
if so, you need to know that these systems don't like to use the heating
coil in the air handler and therefore you need to specify a reheat coil
size and a preheat coil. Also, if you have baseboards in the model, they
don't like to operate very well when set to activate to outdoor conditions.
I always set the baseboard control to thermostat.
Hopefully these few tips help out.
Rob
Rob/all,
I don't have baseboards, it's basic VAV/w reheat system-I was trying to use the baseboards just to see if the zone heating kicks in.
I've attached the zip file, it's giving me the same warning that the zones are under heated and also 1 error that the "hot water loop has zero design flow".
I'm stuck and not sure how to go about it. Please point/help me understand how to go about the error fix....
I appreciate your feedback.
Best,
Nikola