Hello,
Our project is a two floors and 1300 m2 building, opened to four orientations. We have some problems with the unmet hours, because there is no a representative area, where introduce the thermostat of the machine. There is north cold areas, and south warm areas, and an "island" in the middle of a south room which is really warm...
Therefore, can I simulate the baseline building with system 4 (PSZ-HP packaged rooftop) with 3 different machines (one for each zone), in order to introduce three thermostats?
Thanks.
jaume balana
quadrantJune 27, 2013 - 10:28 am
(I am using Design Builder)
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
June 27, 2013 - 2:30 pm
For a system 4 you model it with the same thermal blocks as the proposed design. See G3.1.1 and Table G3.1-7 for guidance.
jaume balana
quadrantJune 28, 2013 - 11:21 am
Hi Marcus, I am sorry, but I think it is still not clear to me...
Just one more question:
For a baseline building, could each thermal block have its own heat pump?
Even though a thermal block is one office of just 10 m2?
Best regards.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
June 28, 2013 - 11:58 am
Does each thermal block in the proposed design have a heat pump?
Look up the definition of thermal block in the standard. Zones can be grouped together. The baseline should have the same thermal blocks as modeled in the proposed.
jaume balana
quadrantJune 28, 2013 - 6:17 pm
Our proposed design has one single heat pump for the whole building. Which supplies hot/cold water (winter/summer) to all fan-coils of our building.
These fan-coils are grouped in some thermal blocks, each thermal block has its own thermostat.
Our problem appears in the baseline building with one single heat pump (system 4 (PSZ-HP packaged rooftop)) which only has one thermostat.
The thermal blocks without thermostat have a lot of unmet hours.
This problem disappears if we assign a heat pump for each thermal block or if we group the whole building in a single thermal block, but the later involves that the proposed design and baseline thermal blocks are not the same.
The unmet hours are killing us...
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
July 1, 2013 - 9:43 am
There should be a heat pump in the baseline for each thermal block.
jaume balana
quadrantJuly 1, 2013 - 9:47 am
Thank you very much.