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[EnergyPlus_Support] Sizing according to ASHRAE 90.1

I have some doubts concerning the sizing of baseline equipment according to APPENDIX G of ASHRAE 90.1.

1) Paragraph G3.1.2.8 of ASHRAE 90.1 states: "System design supply airflow rates for the baseline buildings design shall be based on a supply-air-to-room-air temperature difference of 11°C". I interpret that statement in the following way: if the internal set-point temperature during the winter season is Twin then system design supply airflow rates have to be calculated considering a design supply airflow temperature of Twin + 11°C and if the internal set-point temperature during the summer season is Tsum then system design supply airflow rates have to be calculated considering a design supply airflow temperature of Tsum - 11°C. Is my interpretation correct?
Does the procedure of paragraph G3.1.2.8 of ASHRAE 90.1 regard only the sizing run or even the simulation with the test reference year?
The HVAC system of the baseline is "Packaged VAV with reheat".
In EnergyPlus can I satisfy the request of paragraph G3.1.2.8 using Controller:WaterCoil?

2) In order to calculate the baseline fan motor power I have to calculate the parameter A according to tables 6.5.3.1.1A and 6.5.3.1.1B. Shall I model "fully ducted return and/or exhaust air systems" for every return or relief fan? In the IP edition it is specified that the adjustment is valid only for WCs, but that specification is not present in the SI edition. I don't understand why.
Shall I consider a pressure drop adjustment equal to
125 Pa (0.5 in IP units)
for every "fully ducted return and/or exhaust air system" (see table 6.5.3.1.1B)?
If on one floor there are three WCs where there is a mechanical extraction system. In the baseline model I modelled those WCs as connected to a AHU having both supply and exhaust fans. Shall I consider a total pressure drop adjustment equal to 375 Pa (= 3 x 125 Pa)?

With Regards
Francesco Passerini



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