FIU values the wellbeing of our faculty, staff, students and visitors. We know the Panther community has many questions relating to FIU’s HVAC systems, so below we’ve compiled a list of the most commonly asked questions we’ve received as well as our answers.
If you have concerns about the air quality of any FIU building, please call (305) 348-4600 and place a work order detailing your concerns. Facilities Management in conjunction with Environmental Health & Safety will investigate your concerns.
Were any of the university’s HVAC systems modified during the remote work period?
No. Although we had an opportunity to achieve energy savings by modifying HVAC operating parameters (i.e schedules, setpoints, etc), all HVAC systems were kept on the same operating schedule (typically on for 24 hours a day/7 days a week) and temperature settings were not adjusted. Because of this, ventilation was maintained throughout the remote work period.
Were there changes in maintenance of FIU’s HVAC systems during the remote work period?
No. Facilities Management has continued its scheduled preventive maintenance on all HVAC systems even though the systems have been under reduced loads as compared to historical occupancy.
Has the amount of air changes been increased in buildings?
Many factors influence air change rates and have been considered in detail in consideration of CDC recommendations. All of our buildings are designed to meet the codes and standards in effect at the time of construction and therefore are set to the air change rate specified by the design. (This can vary based on whether a space is occupied or unoccupied.) Because central air handling units supply air to a designed amount of air outlets, increasing the air supply at those outlets beyond the original design air flow rates will overburden the air handling unit and negatively impact the dehumidification capability of the system, which introduces the possibility of mold. Additionally, many spaces were designed without heating capability in the specific space, so increasing the amount of supply air will result in uncomfortably cold temperatures.
How much outside or fresh air is brought into a building?
It varies. The quantity of outside air is a fixed design parameter that takes into account the expected occupancy and use of the building, and is carried into the design of the central air handling units of the HVAC system. All of our buildings are designed to meet the codes and standards in effect at the time of construction. Outside air can range from 100 percent outside air (no recirculation) in laboratories and some office space, varying reduced percentages based on space carbon dioxide measurements, to a fixed amount based on air exhausted from a building from restroom exhaust fans. Central air handling units are designed to cool and dehumidify an amount of outside air required by the codes and standards at the time of construction. Increasing the amount of outside air can possibly overburden the central air handling unit, reducing dehumidification capability and introducing the possibility of mold.
What types of filters are used in the HVAC systems?
Prior to COVID-19, standard HVAC system design and industry used Minimum Efficiency Reporting Value (MERV) 7 or 8 filters for the majority of building requirements. For scenarios requiring reduced particle size such as laboratories or spaces with specialized equipment, MERV 13 filters were used. Following CDC recommendations, Facilities Management evaluated the potential to upgrade filters to minimum MERV 13. After evaluation, testing and confirmation that the central air handling units could overcome the air restrictions caused by the higher filtration of MERV 13 filters, Facilities Management began implementing the upgrades at all facilities. Due to the unforeseen high demand of MERV 13 filters, the process has taken several months but is estimated to be completed no later than November 30, 2020.
Is the university using HEPA filters in the HVAC systems?
No. While High Efficiency Particulate Air (HEPA) filters provide a high level of filtration and significantly reduce particle pass through as compared to MERV 13 filters, equipment must be designed specifically to use HEPA-rated filters. Larger motors and blower units are required to overcome the restriction of air flow caused by the denser filter media. Implementation of HEPA filters in a non-HEPA-rated unit would result in inadequate air flow for all spaces. FIU does not have any central air handling units rated for HEPA filter use.
How often are filters changed in the HVAC systems?
The filtration for the HVAC systems at the university are based on either quarterly filter systems or quarterly/annual hybrid filter systems. A quarterly filter system uses one bank of filters changed every three months. The quarterly/annual hybrid filter system uses lesser-rated filters (changed quarterly) to pre-clean the air and then uses higher-rated filters (changed annually) to perform the final filtration for the air being distributed in the building. Regardless of the system, filter changes have remained on schedule and result in a MERV 13 level of filtration in our buildings.
Can exterior windows or doors be opened to increase fresh air?
Only where buildings or spaces use natural air ventilation (unconditioned air). Examples include detached restrooms, storage rooms and mechanical equipment rooms. Exterior windows or doors to conditioned spaces must be kept closed in order to avoid condensation within the space that can promote mold growth as well as overburden the HVAC system due to temperature and humidity conditions beyond design parameters.
Is ductwork being cleaned?
No. Cleaning of ductwork is not a normal operation and maintenance procedure for FIU facilities. The continuous operation and preventive maintenance of the HVAC systems preclude the need to perform any ductwork cleaning.
Does FIU use Ultraviolet (UV) lights or any other technology in the HVAC system for treating air?
Several central air handling units have UV light systems installed, however, they are designed to improve cleanliness of surface areas in the unit itself and not for the treatment of air flow. Unfortunately, the UV light intensity required for air flow treatment is significantly greater than what is needed for surface treatment. One disadvantage to UV light air treatment systems is that they rely on recirculation in order to disinfect the air in a building. In addition to investigating the feasibility of UV lights, FIU is researching other technologies such as bi-polar ionization, which neutralizes bacteria and viruses in the building’s space. Demand for air treatment technologies has drastically increased with costs increasing as a result of supply and demand. Regardless, FIU is committed to evaluating and choosing reliable and effective systems.