Dear Everyone
I have a question regarding to cooling in electric room such as transformer, UPC room or electrical switchboard room. I use Carrier HAP for LEED modeling purposes for projects loacted in Poland. That spaces are often located in underground floor near parking garage. Technical description says usually that temperature must be max 30C or max 10 C above exterior temperature in cooling time. Sometimes it is hard to obtain any information about thermostats. Sometimes cooling occurs only in emergency conditions.
There are 2 cooling types usually:
1. They are cooled mechanicaly using split AC.
2. Exhaust fan operates only if temperature is too high and cooler air is transferred into space from unconditioned garage area.
My question is if we need to model that cooling process, or can we neglect it. If yes how to set a heat production of these electric units ( power and schedule), because it is hard to predict how they will behave even if we know specific device. I hope that energy use of that equipment such as electricity loses in transformer should not be included in building cost. In Baseline I suppose that System Type 3 should be used in such cases.
I am thinking to include that spaces into "Unconditioned". Previously I set spaces as conditioned, but they operates without any miscellaneous loads so instead of cooling they functioning as heating devices.
Many thanks for any help.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5867 thumbs up
March 26, 2018 - 11:10 am
If the space is conditioned it needs to be modeled. If the space is exhausted it needs to be modeled. It can't be included as unconditioned unless it actually is unconditioned, like the exhaust only example.
You need to determine the load in the space in order to size the equipment serving it, so I am not sure why it is so difficult to determine the load in the space. The design mechanical or electrical engineer should be able to help you identify the load. This issue would be covered in one of the ASHRAE Handbooks as well.
You would model a system 3 (or 4) only if one of the G3.1.1 exceptions apply. One of them probably does so just be sure to cite the applicable one.