Hello! I had submit a project for cs2009, and got some comments confused. The project is a high rise building consists of retails, restaurants and offices.
1. Table 1.4.6 and Table 1.4.7A indicate that system 7: VAV with reheat systems are the only HVAC system type reflected in the Baseline model; however, it appears that the project includes spaces that may meet the requirements of exception (b) of Section G3.1.1 (e.g., data/telecom rooms, kitchens, movie theaters), which may require an additional system type to be reflected in the Baseline model. Additional system types must be included in the Baseline model if an exception to Section G3.1.1 is met. If an exception to Section G3.1.1 is met, revise the Baseline model, as needed, to include the appropriate additional system types for these spaces. In addition, update Table 1.4.6 and Table 1.4.7A, and provide SV-A reports for each additional system type reflecting the changes.
We understand that data rooms and movie theaters have different schedule rather than other spaces need additional baseline system. But why kitchens need additional system? For kitchens, there are only supply fans and exhaust fans. They are not common conditioned area, don’t need to be cooling or heating. In my previous model, I just put the fan power in the electric meter directly. If I was wrong, which system should be used for kitchens? System 3?
2. Table 1.4.4 indicates that 119.1 kW exhaust fans have been included in each model; however, it is unclear if all of the independent fan systems listed in the mechanical schedules provided for PIf4: Schedule and Overview Documents have been modeled in the Proposed and Baseline cases. In addition, it is unclear if the exhaust fans and/or ventilation fans in the parking garage (as applicable) are included in each model. All independent fan systems of the HVAC systems in the actual design must be modeled identically between the Proposed and Baseline models at actual equipment capacities (fan volume and fan power) as required by Table G3.1.10 in the Proposed building column, since the fan design air flow rates and fan power per Sections G3.1.2.8 and G3.1.2.9, respectively, only applies to system types 1 through 8 in Table G3.1.1A. Revise the Proposed and Baseline models, as needed, so all independent fan systems of the HVAC systems are modeled identically between the Proposed and Baseline models. In addition, separate the energy consumption and peak demand power for independent fans and parking garage fans in Table EAp2-4 and Table EAp2-5 of the form. Furthermore, provide sample simulation input summary reports or screenshots for each model reflecting the changes.
What’s the independent fan mean? Is toilet fan and kitchen fan independent? In my previous model, I just put the fan power in the electric meter directly. Is this comment mean that I should set unit ventilator in baseline and proposed model identically not put the fan power in the electric meter?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
March 4, 2016 - 11:40 am
1. A kitchen could meet the peak thermal load difference references in exception b. If the exception applies it would be a system #3.
2. Any fan not tied into the HVAC system fans is an independent fan. Toilet and kitchen fans may or may not be independent. It depends on if they are at all connected to the controls associated with the HVAC system serving that area. An obvious example would be a parking garage exhaust fan or any other exhaust fan serving an unconditioned space. These must be modeled identically in both models, you should report them separately in Tables EAp2-4 and EAp2-5, and mark them as a process load with in the form.
Shenhao Li
Atkins7 thumbs up
March 4, 2016 - 9:22 pm
Thank you!
But in actual design, kitchens have no air conditioning system, only ventilation. Also need to use system #3?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
March 6, 2016 - 4:10 pm
Then the exception does not apply so model the ventilation system identically in both models as a process load.
Shenhao Li
Atkins7 thumbs up
March 6, 2016 - 8:24 pm
OK! Thank you very much!