NYR: Healthy Year, Healthy Building (Part 3) – HVAC System Assessment
As we continue to pursue our resolution for a healthy year and healthy buildings, it is time to assess our HVAC systems.
HVAC stands for heating, ventilation, and air conditioning. Each of these components is essential to achieve the goal of our buildings: creating a safe, healthy, and comfortable environment for our occupants. Occupant satisfaction is affected by the temperature of the building, air movement, and the presence of smells and pollutants, which are all part of our buildings’ indoor air quality and can be impacted by our HVAC systems.
Part of reaching our goal to have a healthy building is measuring and monitoring energy consumption. HVAC systems in commercial buildings typically account for about 40 to 50 percent of the entire energy bill. This fact makes the HVAC system a crucial place to focus when attempting to optimize our building’s health. Energy efficiency efforts are not only key for maximizing our bottom lines, but also being responsible stewards of our environment.
As previously discussed, energy efficiency and IAQ efforts can be achieved by some of the same actions, mostly associated with our HVAC systems. As we evaluate our HVAC system, we can focus on balancing both IAQ and energy efficiency to achieve a high performing and healthy building.
Measuring and Monitoring IAQ and Energy Efficiency
Are you currently measuring and monitoring your IAQ and your energy efficiency? It is through measuring and monitoring that you will be able to track your progress of creating a healthier building.
How to measure and monitor IAQ
- First, walk through and interview occupants to assess comfort level.
- Using the information gathered, set up data recorders in various parts of the building to monitor CO2, temperature, and relative humidity in order to assess comfort, ventilation, and building operations schedules.
- Taking a deeper look at indoor air quality would require measuring levels of CO, NO2, volatile organic compounds (VOC), and relative humidity both inside and outside the building.
How to measure and monitor energy efficiency
- Look at your energy bills to identify trends.
- Benchmark your energy use through the EPA’s Portfolio Manager tool. Your Energy Star rating will compare your energy use to other buildings similar to yours. This will allow you to see how much room for improvement you have with your energy use.
- Use an online management dashboard, such as EnergyPrint, to automatically track the building’s energy usage. This saves time and eliminates the human error factor that often comes with task of data entry.
For more information, read our post, The Four A’s to Energy Efficiency: Accumulate, Analyze, Act, Assess
Now we need to do a building walk-through. Here are some things to look at:
Basic equipment knowledge. By collecting some basic knowledge about each piece of equipment, we will better understand each piece in the system and the system as a whole. This information will be helpful in determining how well the equipment is performing and help us calculate the ROI if we want to look at replacing it.
Age. How old is the equipment?
Life Expectancy. What is the life expectancy of this type of equipment? Is it trending toward that life expectancy?
Maintenance and repair record. How often is this equipment maintained? How often does this equipment need repairs?
Ventilation. How is the ventilation in the building? Over half of occupant complaints about IAQ are a result of ventilation problems.
Air intake. Are the air intake sources for the building properly placed? Are they too close to pollutants such as exhaust outlets, standing water, or trash containers? Are the air intake sources clear of any obstructions?
Dampers. Are the dampers working? Do they open at the appropriate time? Are they obstructed from opening or stuck open?
Filters. Are the appropriate filters for the system and building being used? Are the filters dirty or clogged? Ineffective filters can allow pollutants, dust, and dirt to circulate in the building, and dirty filters can cause the system to work harder, losing efficiency.
Outdoor air. Is there enough outdoor air circulating in the building? A lack of outdoor air can cause stale air and the accumulation of indoor pollutants and occupants’ germs. Calculate the amount of outdoor air by measuring CO2 levels.
Controls. Are all controls operational? Are all calibrated properly?
Thermostat. Is the thermostat set at the correct temperature for the season? Are all of the setback temperatures correct or were they accidently changed the last time someone overrode the system? Is the thermostat calibrated properly? If the thermostat is not properly calibrated, reaching the building’s desired temperature can be difficult and can cause the system to be overworked.
Clock. If there is a clock associated with the thermostat or other controls, make sure it is set properly. An unsynchronized time and date could interfere and distort any adjustments scheduled for the HVAC system.
Coils. Are the coils clean? This means not only cleaning the outside casing of the unit, but also occasionally taking off the casing to clean the actual surface of the coils. A thin layer of dust on coils can make the system work 10% harder, increasing energy use.
Motor connections. Check to make sure that all motor connections are tight. Loose connections can cause a loss in efficiency.
Leaks – refrigerant, water, and air.
Refrigerant Lines. If the system uses refrigerant, check for leaks in the line.
Water Lines. If the system uses water, check for any leaks in the line. Be sure to clean up any standing water associated with those leaks since standing water can cause mold growth which is detrimental to IAQ.
Air Ducts. Are the air ducts tightly sealed? Is there air escaping where it shouldn’t? Are the air ducts clean and free of condensation? Condensation in air ducts can create a breeding ground for mold, which can then be carried through the air ducts and spread throughout the building.
As an additional resource, the EPA has some excellent forms to help assist you in performing a full building audit, specifically focused on IAQ. And remember, we are in this with you, so we can certainly help you perform an audit of your building.
Once we have looked at the HVAC systems in our building, it is time to check out our plumbing systems. Join us next week as we breakdown what to look at in terms of our plumbing systems.