Since the start of the pandemic, many commercial buildings have been left unoccupied for long periods of time. But as restrictions lift and people start to return to work, building owners must make sure to perform the necessary maintenance on their HVAC systems, which have likely been running minimally — if at all.

Follow these guidelines to get your HVAC system operating safely and efficiently before your building opens up to employees and customers.

• Routine maintenance is always recommended, but now is the time to add expanded maintenance procedures before building occupants move back in. Plan to block off at least one full week depending on building size.
• Depending on how long your facility has been shuttered, check with local building officials to determine if an inspection needs to take place. This is especially true for steam generators and high-pressure boilers.
• Visually inspect all equipment for signs of leaks, dust/dirt accumulation or other damage. If your system has been offline for a while, you could be dealing with bacterial growth on coils, drain pans, etc.
• The same applies to chillers and boilers that have been fully turned off — stagnant water leads to decreased efficiency and the potential for reduced life of equipment. Plus, sitting water tends to grow mold, bacteria and other harmful contaminants that present a hazard to building occupants, so it’s important to check water quality prior to reopening.
• Check air systems and outdoor air intakes for obstructions and debris. Clean and upgrade air filters and make sure filters fit tight in their frames.

For more recommendations on preparing a building for re-occupancy, visit ASHRAE’s COVID-19 Preparedness Resources webpage.