CBECC-Com MF High-Rise Prototype

[GoogleCodeExporter]

I have attached a model that we are trying to make exactly the same as the 
prototype (exactly compliant). We have compared the -ab and the -ap file and 
found the following discrepancies/questions:

1) In line 9413 of the -ap file, the boiler pump head is showing up as 352, 
even though it is only 60 in the user interface. I believe this is also making 
the pump power much higher. How can I fix this?

2) The model is currently failing, largely due the DHW system, which the -ab 
file does not even have. I tried deleting the DHW system, but an error tells me 
that the apartments require either an SHW or DW system. How can I fix this?

3) This building is 10 floors, and I would like to make the 8 floors in the 
middle all replicates. Is the correct procedure to add a multiplier of 8 in all 
of the following places?:

- Envelope tab

- Building data -> Stories = 10 (this doesn’t seem to update the floor area)

- Building story data -> Story Multiplier = 8

- Under Building Model Data -> Space Data -> What changes the ‘multiplier’ 
above flr-to-clg Ht?

- Mechanical tab

- Building model data -> Zone System Data -> Count = 8

- Building model data -> Thermal Zone Data -> HVAC Zone Count = 8

- Anywhere else? Any of the places above that should stay ‘1’?

I may be working on this over the holiday, so any help soon would be 
appreciated. Thank you!

Original issue reported on code.google.com by f.le...@gmail.com on 26 Nov 2014 at 7:55

[GoogleCodeExporter]

You have a significant problem with your model in that you are using the hot 
water system for service hot water, which is not allowed.  In version 3a, due 
to be released as soon as the CEC certifies it, this will be trapped and an 
error thrown.  Once you have a configuration error like this, subsequent issues 
may appear as a result that appear to be independent.

Regarding the Recirculating DHW system, the baseline for DHW systems serving 
residential spaces is that they will have a solar fraction of 20%.  You had a 
solar fraction of 0%, so that will cause a negative compliance margin.  
However, when I put in a 0.20 I am still getting a negative compliance margin 
for DHW, which I believe is due to the issues above.  You should add another 
fluid system of type ServiceHotWater, with supply and makeup fluid segments and 
a storage hot water heater of the appropriate efficiency (make sure you include 
a thermal efficiency input along with the efficiency input indicated based on 
capacity).  Assign the supply segment to the office space.  

Fluid systems intended for domestic hot water are type ServiceHotWater or 
RecirculatingDHW.  HotWater fluid systems are intended for heating only.  
CBECC-Com does not currently support heating and domestic hot water heating 
from a single boiler.  

The corridors do not have any ventilation, you need to assign a ventilation 
system to serve these spaces.   Ventilation air is required for corridors.  

The pump head for your hot water pumps is being increased because of the motor 
HP assigned to these pumps.  The rules calculate the rated pump power from the 
flow, head and efficiencies, and then compare that to the rated motor power.  
If the rated power is less than the horsepower of the next smaller motor size 
from a table of motor sizes, the head is increased such that the power is 
consistent with the assigned motor capacity.  Essentially, if the motor size 
and rated power are inconsistent, the head is increased to bring them into 
rough alignment.  When I changed the rated motor power to 0.5 HP, the head was 
changed to 89 ft, so you will presumably want to make it smaller still, 0.25 
perhaps.  

I strongly recommend that you update to version 3a, which will be released as 
soon as we receive the certification notice from the CEC, which we have been 
expected for several days now.  In the UI the multipliers on the story are now 
echoed on the space dialog.  The only thing I think you missed in your 
multipliers below is to put a count of 8 on the “M Floor Base Air” air 
system.  Also, at the thermal zone, the HVAC Zone Count stays 1, this is to 
indicate that the modeled thermal zone is representing multiple zones in the 
building.  In version 3a, the Zone Multiplier is correctly echoing the 
multiplier of 8.  

Original comment by rhedr...@archenergy.com on 2 Dec 2014 at 6:31

• Changed state: WontFix