NYSUT Questions about Building Ventilations Systems for:
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Monroe One BOCES
O’Connor Academy, Bldg 9, 10
25 O’Connor Rd, Fairport NY 14450
HVAC FAQS: O'Connor Academy
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Who maintains ventilation system?
District Personnel
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Where are the outside air intakes?
Located on the roof.
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How is the building zoned?
The gymnasium has its own unit and the E-2 shop has its own units. Elsewhere, each room has its own coil with its own filter which provides cooling through chilled water or heating from hot water. The outside air is mixed with the exhaust air in the plenum above the ceiling. The building 10 plenum is separate from the building 9 plenum. Unlike most school buildings, this building does included its corridors within the heated and cooled areas.
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Does the building have an economizer?
No
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Is outside air increased to the highest extent possible based on daily weather conditions, at least above the minimum recommendation of 17 CFM of outdoor air per person, or approximately 20% outdoor air?
Yes. 20% outside air is now the minimum level of outside air brought in whether heating or cooling.
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Is HVAC filtration increased to the highest level possible based on the capacity of the system?
We have installed high grade commercial filters based on the manufacturer’s operation manual recommendation. Currently this is at least MERV 8. While it is true that ASHRAE is recommending MERV13 for new building designs, they are NOT recommending installation higher rated filters to be installed without careful study of each system. Their latest update: “Select filtration levels (MERV ratings) that are maximized for equipment capabilities, use MERV 13 if equipment allows, while assuring the pressure drop is less than the fans capability. See Filtration Upgrades.” (ASHRAE, 2020, Re-Opening Schools and Universities, Retrieved from https://www.ashrae.org/technical-resources/reopening-of-schools-and-universities, 2020 Aug 17.) Please note that there are caveats throughout the ASHRAE guidance, they state the optimum, then the limit. Those of us in O&M are very concerned with this issue. We continue to evaluate the performance of our units. They work the hardest in the summer and so we are evaluating the winter performance as a separate issue from the summer performance. We do not want to reduce airflow, cause the units to suck in unfiltered air through gaps in the unit of duct work, nor overwork the units to failure. A comparison might be that a MERV13 filter is like a N95 mask v. surgical mask which is more of MERV8. The N95 is superior to a surgical mask and the surgical mask out performs most reusable cloth face coverings. But, over and over again it has been proven that the cloth face covering works.
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Are HVAC systems kept running longer hours, up to 24/7 if possible, and at least 2 hours before occupants arrive and the last person leaves the building? What is the HVAC operating schedule?
We are increasing the HVAC runtime. We program them to operate as if occupied for at least 2 hours after their scheduled use is completed and at least 2 hours before staff arrive. It is our objective to have not less than 4 room air turn overs before reducing to the unoccupied schedule and to have at least 2 room air turnovers before opening in the morning. The average schedule will be 5 AM – 6 PM. The units may run longer depending upon the outside weather. It is not that the units are shut off but rather that the desired set point is changed to maintain 80 degrees in the cooling season and 60 degrees in the heating season. We can override the schedule at any time. If a nurse or director alerts O&M of a suspected COVID-19 case, we can place the area of concern into a high outside air intake to purge the area, and extend the run time. Similarly, we can re-schedule for special events.
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Are portable room air cleaners with HEPA or high-MERV filters provided in areas where there is high occupant load or areas of poor ventilation?
We do not have high occupant loads, and occupant loads have been further reduced by the new schedules, and we have good ventilation in occupied areas. Our class sizes are relatively small.
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Are upper room and/or portable UVGI devices used in areas where there is high occupant load?
UVGI devices are specifically not approved by SED because they feel their safety is not proven. Regardless, we do not have high occupant loads.
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Are bypass energy recover ventilation systems that could leak potentially contaminated exhaust air back into the outdoor air supply deactivated?
These do not exist.
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Are temperature and humidity levels maintained within the established ASHRAE seasonal guidelines with temperatures between 68 F to 74 F in the heating season and 72 F to 80 F for the cooling season and humidity between 40% and 60%?
We do maintain these temperature and humidity targets without issue except in the winter where we have noted humidity drops below 40% when it is very cold outside and when school is out of session.