Tag: Indoor Air Quality

COVID-19 and Building Ventilation

Posted on by Lindsey Burbee

Keeping your HVAC breathing through the Covid-19 pandemic.

 

The United States continues the fight against COVID-19, many reopened businesses are concerned about indoor air quality. As a result, new requirements are being implemented for the public’s safety.

Recently, New York allowed for the reopening of shopping malls but with a mandate from Gov. Andrew Cuomo: Update HVAC filters with at least a MERV-11 rating to capture the potentially airborne coronavirus particles. Likewise, Colorado’s Denver Public Schools unanimously approved Denver schools to get ventilation upgrades to help stem the spread of coronavirus. So what do these guidelines mean, and could other states follow these policies?

 

 

HVAC Filters

Minimum Efficiency Reporting Value (MERV) is used to measure the effectiveness of air filters on a scale of 1 to 16. The higher the MERV rating, the greater the filtration, i.e. the smaller the particles it can catch. The Centers for Disease Control and Prevention (CDC) recommends to improve central air filtration to the MERV-13 level (or the highest compatible with the filter rack) and to seal edges of the filter to limit bypass.

 

 

MERV filter rating for HVAC systems
Model of MERV filter ratings. (Source)

 

However, updating an HVAC system’s air filters may not be as simple as it sounds. For instance, a common factor that will get overlooked is that most HVAC systems that were designed for lower MERV filters (likely most of them) will need to be rebalanced for the new filters. The higher the MERV rating, the better the filtration but also the higher the static pressure (or resistance) that the fan must work against, resulting in a drop in airflow. The reduced airflow could cause comfort problems and even frozen coils. To prevent these issues, the airflow will need to be measured with the new filters installed, and then the fan speed will need to be increased to achieve the designed airflow.

Yet this is still not a “one size fits all” solution for all. Many HVAC units cannot handle the higher-rated filters. Using a filter with a higher MERV rating may cause the motor to burn out. This is why it is important you have a trained technician review your unit before making any changes.

 

 

Other Building Ventilation Recommendations

In addition to replacing filters, ASHRAE recommends the following actions, with the ultimate goal being consistent and frequent air changes:

 

  • Increase outdoor air ventilation (use caution in highly polluted areas); with a lower population in the building, this increases the effective ventilation per person.
  • Open minimum outdoor air dampers, as high as 100%, thus eliminating recirculation. (During mild weather, thermal comfort or humidity within a facility normally wouldn’t be affected. During extreme weather, this clearly becomes more difficult to control.)
  • Consider portable room air cleaners with HEPA filters.
  • Consider Ultraviolet Germicidal Irradiation (UVGI), protecting occupants from radiation, which is particularly in high-risk spaces such as waiting rooms, prisons and shelters.

 

 

Developing Solutions

While the experts are recommending the above items, they are not mandatory across the country. States’ policies vary. Not to mention that COVID-19 research is still developing.

 

 

COVID-19 changing building ventilation

 

The result, in the near term, is likely to be a patchwork — some commercial buildings, schools, colleges, and other facilities will make investments, while others will not. One example of an organization making the investment to fight COVID-19 is KIPP DC, a publicly funded and privately operated network of seven school campuses with 1,200 employees and 7,000 students. KIPP DC has taken huge measures, working to find the ideal system optimized to filter the coronavirus.

 

 

KIPP DC’s Coronavirus Filter System (Source)

 

 

Hire Melink to Help

Overwhelmed and not sure where to begin? Melink employs a 100% self-performing, NEBB-Certified national network of Test and Balance (T&B) HVAC technicians that can quickly deploy to assess mechanical systems, verify airflow rates in accordance with ASHRAE 62.1 standards, and perform any traditional T&B work.

We have multiple, long-standing relationships with some of the largest national restaurant, retail, hotel, and supermarket chains. These relationships began because those partners liked the idea of having just one third-party company to coordinate. Melink handles all their properties by objectively verifying that the HVAC systems were installed and are working as expected.

We are here to help you navigate the ever-changing recommendations and regulations of the pandemic. Let us help you keep your doors open while helping protect your employees, customers, and equipment. Contact us.

Becoming an Intelli-Hood Sales Engineer (During a Pandemic)

Posted on by Lindsey Burbee

Sales Engineer. These are two words that most of us have a clear understanding of their respective meanings. But what about when they are put together? Well, I ‘m not sure what to expect either, but it sounded like a challenge, and I like those. I’m new to the Demand Control Kitchen Ventilation (DCKV) industry but well-versed in technology and mechanics due to my background. So, when I took the role of a Melink Intelli-Hood Sales Engineer, I felt well prepared.

Then, enter COVID-19.

Onboarding plan? Derailed. Customer visits? Cancelled. Installations with field service techs? Not attending. How was I supposed to embrace my role and be a valuable addition to the team?

 

 

What Next?

That’s where my Melink family stepped in. To continue with business “as normal,” we, like other companies, took advantage of virtual meetings, trainings, lunch-and-learns, and other digital tools. These tools were not thought about or utilized even just 10 years ago! As the pandemic unfolded, our work progressed, thanks to these digital tools. I immediately saw the value in my new role and Melink’s value to their customers.

For instance, indoor air quality became a topic of daily conversation. Essential facilities, like grocery stores and hospitals, were now on the front lines. I helped get Intelli-Hood® kitchen ventilation controls into these areas and ensured first responders had healthy air.

You see, Intelli-Hood learns to optimize your kitchen ventilation by using temperature probes paired with infrared optical sensors. The optics pick up on airborne contaminants in the form of smoke and then trigger the variable frequency drives. The exhaust fan’s variable frequency drive (VFD) adjust to the appropriate speed to ensure adequate evacuation of the effluent. Smoke being present does not have to mean that heat is, which is one more way that a Melink Intelli-Hood control system ensures continuous capture of all effluent. As if that was not beneficial enough, the system is also ensuring that more of the pre-conditioned air is staying in the occupied spaces instead of being wastefully exhausted from the kitchen due to continuous discharge ventilation.

 

 

Looking to the Future: Customized Solutions

Pre-COVID-19 and now, I spend each day as a Sales Engineer building customized quotes for our customers’ unique needs. As requests for new construction sites roll in, I work with my Business Development Manager to go through the plans for each site, reviewing the kitchen designs and ventilation requirements, as well as requirements that have been called out by general contractors and food service consultants. Every job requires different exhaust hood types; fan types and horsepower; and temperature monitoring preferences, as well as the possibility of tying the system into a building’s BACnet. All of these items and more are taken into consideration when preparing an accurate, customized quote for our customers.

Thus, these last few months of working in Virtual Corporate America have helped me realize just how adaptable our team at Melink — and our Intelli-Hood controls — really are. COVID-19 or not, these control systems are improving the health and wellness of employees and customers in thousands of locations worldwide, all while being the most energy efficient DCKV system on the market. And the umbrella of Melink solutions extends to other areas, too. When you pair an Intelli-Hood control system with solar panels, a PositiV® unit to monitor building health, and a high-quality Test and Balance plan, you really cannot ask for a more efficient and energy-saving space.

I may only be finishing my first quarter here at Melink as a Sales Engineer, but already I have felt the satisfaction of knowing that what I am doing is making a difference.  We really are making the world a better, greener place, one building at a time.

Intelli-Hood system

COVID-19 Closures: Mitigating Damage to Unoccupied Buildings

Posted on by Lindsey Burbee

Dealing with COVID-19 Closures

Many U.S. states are working to flatten the curve as businesses are impacted by COVID-19 closures. The “stay at home” or “shelter in place” orders have limited human interaction in attempt to prevent spreading the virus. Additionally, many companies across the country opted to temporarily close facilities, preventing employees from contracting the disease. With shutdowns it’s become increasingly difficult to determine a facility’s condition, or to repair any issues developing while the facility is unoccupied.

 

 

COVID-19 closures of restaurants

 

Damage to Unoccupied Buildings

Consider these scenarios that could arise in an unoccupied facility…

Humidity

 

  • Buildings in coastal regions may experience high humidity that goes unnoticed, which can in turn lead to mold growth. Imagine if the facility is a retail store. The end-result might mean thousands of dollars of damaged, unsalvageable clothing merchandise.
  • Think about a restaurant or bar. There may be hundreds (or thousands) of dollars of alcohol in stock, going untouched through the COVID-19 crisis. Corked bottles of wine are not exempt from the effects of dry indoor air. Extremely low humidity levels can slowly chip away at a cork, leaving room for air in the bottle and ruining the flavor. The ideal humidity level for wine storage is 60%.
  • Another thought for restaurant facilities: A humid environment allows mold growth to fester. The COVID-19 shutdowns began suddenly for many facilities. Did kitchen staff have adequate time to scrub walk-ins, pots, and pans? Were grease traps thoroughly degreased? These are potential breeding grounds for mold during non-occupation.

Moisture

  • If indoor moisture levels drop too low — like cooler climates that are shifting from winter to spring temps — wood can begin warping. For instance, wooden window frames can shrink, making them difficult to open. This can potentially create gaps that let in cold, dry air.
  • Low indoor moisture can also lead to peeling or separated wallpaper and cracked paint on plaster walls. What if you returned to your facility, only to realize you’ll need professional painting or remodeling services?

Mulit-Purpose

  • Contemplate multi-purpose facilities, like an apartment complex with retail or dining space on the first floor. Completely shutting down HVAC airflow to unoccupied businesses could lead to uneven air flow and temperatures throughout the larger building.

The bottom line: Scenarios like these will go unnoticed and unrepaired until employees return to their facilities. Only then will they uncover the damage caused by an unoccupied month.

 

 

Preventing Facility Damage During COVID-19 Closures

While these issues seem frightful, many state governments have kept issues like this in mind when mandating shelter-in-place orders. Seeing value and necessity in essential services, many states are allowing skilled trades such as HVAC technicians to continue working. During quarantine, let technicians be the eyes and ears at your facilities to ensure critical issues didn’t develop, and further delay reopening.

In addition, this downtime can also be the ideal occasion to have technicians visit the facility to address any known issues or to perform preventive maintenance. Maybe there is a repair the facility manager has been putting off because its fix requires closing a typically busy corridor or lobby area. By addressing this work now while the facility is shut down, managers can limit future downtime, employee inconvenience, and lost profit.

And as a preventative measure for the duration of this closure or in preparation of future closures, consider installing sensors to remotely monitor a facility’s indoor air quality levels through relative humidity, temperature, building pressure, and CO2 checks. A system like Melink Corporation’s PositiV® building health monitor can remotely track and trend building health, plus send alerts to the facility owner or manager when the system detects measurements outside its set parameters. While a facility may not have this in place to combat the current COVID-19 closures, it can be installed now to prepare for future unplanned closures or even a vacation (Facility managers need a break at some point, right?!).

Coronavirus & Indoor Air Quality

Posted on by Lindsey Burbee

Now, maybe more than ever, many businesses are concerned about indoor air quality (IAQ) to protect employees and customers from coronavirus. With the current spread of COVID-19 across the globe, it is important that we are all taking the necessary steps to reduce the spread of the virus. As part of this, it is important to recognize how your HVAC system can impact your IAQ during long hours of social distancing, as well as steps that can be taken to limit the spread of the virus in buildings.

In a normal year, the typical American spends 90% of his or her time indoors. With current guidelines about social distancing, this number is expected to increase over the next few months. Prior to recent events, the American Medical Association stated they believe 50% of illnesses are caused, or aggravated, by polluted indoor air. Furthermore, per the EPA, indoor air contains two to five times more pollutants than typical outside air.

 

 

 

So what does this mean for the COVID-19 crisis? Now that we have learned the novel coronavirus can be spread via airborne transmission when in close contact, there is the possibility that the HVAC system could cross-contaminate. That means air from an infected person could recirculate through a facility’s HVAC system and infect another individual. An example of this is how cruise ships experienced severe outbreaks. All cabins share an HVAC system, which is working as a mode of transmission from one individual to another.

While this risk of shared indoor air cannot be completely eliminated,
there are a few items that can be addressed to reduce the potential for
transmission through the HVAC system including:

 

  • Enhanced Ventilation & Ventilation
    Effectiveness
  • Source Separation
  • Air Filtration
  • Operable Windows

First and foremost, facilities should ensure their HVAC
equipment is bringing in the correct amount of outside air required by the
engineered designed plans, as well as managing the pollution and exhaust from
your building properly. To further mitigate this risk, one should attempt to
increase the percentage of outside air being brought into a facility to a
higher percentage than minimally specified. In doing this, the equipment will
reduce the amount of air being recirculated through a building. This will not
only reduce “shared air,” but will also decrease levels of CO2 and other indoor
air pollutants that can create an uncomfortable, or unhealthy, facility.

For a residential facility, where air source isn’t as easily controlled, it can also be helpful to open windows to bring in fresh air to any given room. In addition, it is worth verifying that any fresh air being brought in is being evenly distributed. If it isn’t, certain rooms may have less air turnover, meaning that the air isn’t circulating in and out of the facility properly.

The next few months may be difficult with longer hours than normal spent indoors. It is important that we are all taking steps to minimize the spread of coronavirus and other airborne illnesses both now and in the future. Melink offers products and services specifically designed to track, trend, and improve indoor air quality. Click to learn more about our HVAC test and balance services or PositiV® building health monitor, or contact us today. Our techs are the certified pros in indoor air quality — let us help you mitigate your risk while protecting employee and customer wellness.

 

Coronavirus
Source: Centers for Disease Control and Prevention

Air Quality’s Impact on Health

Posted on by Lindsey Burbee

Indoor air quality (IAQ) can influence the cold/flu season. According to the American Medical Association, 50% of illnesses are caused or aggravated by polluted indoor air. The U.S. Environmental Protection Agency (EPA) believes this is because indoor air contains two to five times more pollutants compared to typical outside air.

While the average person spends 90% of their time indoors, many groups of people considered to be “high risk” spend even more time indoors. These populations include but are not limited to babies, the elderly, and those with health conditions. So when you consider the ample amount of time people are spending indoors with potentially polluted air, it is easy to understand how IAQ can be linked to sickness. In fact, IAQ poses such a large risk to human health globally that the EPA recognizes it as one of its top 5 health hazards.

 

 

Sick building showing indoor air quality

 

While most people think that poor IAQ is easily noticeable because they can sense it through vision or smell, this is not normally the case. Many times, the IAQ in a facility may be poor because the CO2 level is far higher than recommended. Typically, a “safe” level of CO2 is between 400-1,000ppm, but levels can reach as high as 2,000ppm. At this high level, occupants can experience headaches, sleepiness, decreased cognitive function, and increased heart rates.

To ensure that CO2 levels are kept in check, it is best to have a building health monitor (such as PositiV) installed to examine these levels. If the CO2 level is above the 1,000ppm mark, it is best to examine the outside air intake on the air conditioning equipment to ensure the facility is receiving the proper air changes per hour and enough fresh air is entering the facility.

Love Is in the Air (and So Are Dangerous Gasses)

Posted on by Lindsey Burbee

With Valentine’s Day upon us, we can’t ignore the fact that love is in the air and all around. The season of love and Cupid’s magic are hard to ignore. Unfortunately, lovebirds, that isn’t the only thing you will find in the air this season. Dangerous gasses called Volatile Organic Compounds (VOCs) are lurking everywhere (up to 10 times higher indoors), and could be turning your stomach butterflies into nausea and vomiting.

VOCs include a variety of chemicals that are emitted as gasses from certain solids and liquids, including common household products. These are products that most people have around their house and place of business, such as paints, aerosol sprays, cleansers and disinfectants, hobby supplies, and even dry-cleaned clothing! Who knew? Items that may be littered around your space are known to cause both short-term and long-term adverse health effects including but not limited to irritation, nausea, liver and kidney damage, and possibly cancer. Scary stuff, right?

So how do you reduce your risk and exposure to these nasty gasses? First and most importantly, increasing ventilation when using these types of products is key. For commercial buildings, experienced HVAC engineers can ensure a building has enough air changes per hour to properly replace the indoor air with fresh outside air.  This measurement is determined by the building capacity, as well as how the space will be used. For example, by code, a restaurant requires an average of 20 CFM of fresh air per person, so if the max occupancy is five people, the building will require 100 CFM of fresh air at minimum to ensure a healthy amount of air changes per hour.

While this seems like a simple way to ensure a building’s air is not filled with common air pollutants including VOCs, this is not always the case. The amount of outside air entering the building is set by the rooftop unit (RTU) to match the designed value for the facility. This value is then verified through a test and balance technician measuring the airflow and resetting it to the proper amount. Without this final verification, your building may be receiving improper amounts of fresh air, which can leave your building and its occupants susceptible to higher concentrations of air pollutants.

Other steps to take to reduce risk in your home and business are:

  • Follow label instructions carefully. Always meet or exceed label precautions.
  • Throw away partially full containers of old or unneeded chemicals safely. Only buy in quantities you will use soon.
  • Keep exposure to paint strippers, adhesive removers, aerosol spray paints, auto exhaust, and tobacco smoke to a minimum.
  • Use integrated pest management techniques to reduce the need for pesticides.

Don’t let VOCs ruin the love for you this Valentine’s Day! Take the right steps to minimize your exposure and keep the magic of the season alive.

What causes poor Indoor Air Quality?

Posted on by Lindsey Burbee

Indoor Air Quality (IAQ), or the condition of the air inside a building, is a very important building health attribute that can affect the comfort, productivity, and wellness of a facility’s occupants, workers, students, and visitors.

Poor IAQ has been linked to several symptoms such as headaches, fatigue, trouble concentrating, and dizziness, as well as irritation of the eyes, nose, throat, and lungs.  The more prolonged the exposure, the greater the effect.  Here are five common factors that contribute to poor IAQ:

Negative Building Pressure – A negative building, one in which the pressure inside is less than the pressure outside, will draw air through doors, windows, and any other openings in the exterior.  This air is unfiltered and unconditioned, so whatever is outside comes inside, including high humidity, pollutants, insects, and so on.

Inadequate Fresh Air Ventilation – Fresh outside air is introduced into a building through a series of fans and dampers. Relief air is also evacuated from a building in a similar manner. These air systems must be properly set up and adjusted for the correct amount of fresh air needed for the building based on its use and occupancy.

Insufficient Contaminant Capture – Contaminants that are produced from various operations within a building, such as heat and smoke from cooking, steam from dishwashing, or pollutants from work processes, are captured and contained with systems of fans and canopies.  These systems must be properly configured and adjusted for each unique process in order to capture and contain the effluent produced.

Improper Air Distribution – The various spaces within a building have their own ventilation and pressurization needs, so the air movement inside a building is vital.  The air distribution systems must be properly configured and adjusted throughout the entire building.

Deficient HVAC Maintenance – The various fans, dampers, filters, coils, and other devices comprising a Heating, Ventilating, and Air Conditioning (HVAC) system must be cared for, and maintained correctly and frequently in order to support proper indoor air quality.

Is Your Business Haunted Or Is It Something Worse??

Posted on by Lindsey Burbee

Has your business experienced…

Zombie Levels of Productivity

Poor levels of fresh outside air leading to insufficient IAQ can decrease air quality. According to a study done by Harvard University, productivity levels can be increased by up to 61% when the proper amount of air quality is introduced into the space, and can be increased by 100% when doubling the ventilation.

Chills Running Down Your Spine or Sweaty Palms?

Improper heating and cooling due to an unbalanced building means air is distributed unevenly which creates temperature variation. Hot and cold spots around your building are probably signs of an unbalanced building, or are they??

Something Strange in the Air?

Air drafts can be caused by too much air being delivered to certain areas and then the air moves between rooms in order to reach an equilibrium of pressure.

Musty Odor Means Something Is Lurking

When air isn’t cycled properly through the building on a regular basis and you let the humidity get too high, you provide a breeding ground for bacteria and mold. Considering the average adult spends 92% of their time indoors, that means a lot of time breathing in these gross pollutants!

Mysterious Noises No One Can Explain

Have you been startled by an abrupt sound somewhere in your building that you can’t pinpoint? Poorly sized belts or pulleys can cause RTUs to squeak as they are operating, and duct leakage has been known to create some creepy noises as well.

Doors Opening and Closing With No One There

Pressure differentials caused by an imbalance of air being delivered to certain rooms can make doors open and close on their own.

Don’t call Ghostbusters just yet! There is a good chance you building is not actually haunted but instead just needs a good balance. Many of the above culprits can be easily fixed, and will not only improve your building’s health, but the health and productivity of everyone inside (one study shows estimated productivity benefits from increased ventilation could be as high as $6,500 per person per year!).  Learn more on what a building balance is here or contact us for more information on how to get rid of the pesky (and creepy) issues you are having!

A Balancing Act: Air Balance is an important part of HVAC maintenance

Posted on by Lindsey Burbee

When it comes to HVAC, no news is good news for restaurant facility managers. When you start hearing chatter about the building being hot and humid, drafty, smoky or uncomfortable, you know a problem has already taken root. It’s like a piano being out of tune. In addition to unhappy customers and employees, comfort issues are indicators of energy inefficiency within a system and air balance issues. So, what can facility managers do to prevent comfort and energy threats?

Identifying Common Problems

“Facility managers need to be trained on air balance and push it to their service contractors,” recommends Jeff Dover, resource manager at RFMA.

A good place to start is to gain a foundational understanding of building pressure and common HVAC deficiencies along with following seven easy steps to bring your restaurant back into tune. Most importantly, learn how to look for negative building pressure. Remember, the goal is to stay slightly positive in building pressure.

There are three methods to identify negative building pressure. The first and most reactive method is to monitor signals that your building is negative. These signs are hot/cold spots, entry doors that are hard to open, poor smoke capture, humidity, condensation dripping from diffusers and drafts.
Second, you can measure the building pressure yourself or with the help of your service contractor by using a pressure reading tool such as an anemometer to get a ballpark pressure reading. The third and most accurate method is to hire an air balance firm to check the facility’s building balance once a year. If comfort-related issues or a negative building pressure reading are observed, then an air balance needs to be scheduled.

Investigating the Cause

What causes a building to become negative or unbalanced? The usual offenders are equipment deficiencies, improper preventative maintenance programs, and adjustment errors such as kitchen staff fiddling with thermostats or service contractors opening or closing dampers.

 Here are 10 example deficiencies you or your service contractors should be on the lookout for:
  1. Exhaust fans in poor condition
  1. Supply air leaking above ceiling
  1. OA dampers improperly installed
  1. Exhaust fans not sealed to curb or hinged correctly
  1. Dirty compartment/coil in the RTU
  1. Tops of diffuser not insulated
  1. Filters improperly sized for hoods
  1. MUA not operating properly
  1. Dirty indoor/outdoor filters
  1. Worn/broken belts

Achieving Air Balance in HVAC

Once you’re ready to bring a facility back into tune, there are seven easy steps to complete. These steps may be completed by the facility manager alone, but are more likely in partnership with a service contractor. To get started, pull out the facility’s previous balance report to use as a base line for data.

One Principal Engineer at a hamburger fast food chain overseeing thousands of locations explains how her team uses the air balance report to get started with troubleshooting comfort issues.

“The reports really are my first line of defense when someone says ‘Hey, my store is cold/hot/humid,’ she points out. “The first thing I do is pull out the TAB report and see what it says. I look at the punch list and ask was anything wrong? Not fixed? It helps when I have to remotely assess or diagnose problems.”

7 Steps to HVAC Balance

Whether the previous air balance report has been reviewed or not, proceed to the following steps:

  1. Ask the onsite restaurant managers what the complaints are from employees and customers.
  1. Turn on all HVAC equipment.
    • Verify thermostats are set to “FAN ON”
  1. Check building pressure with the flame test in different areas around the restaurant (Figure 3)
  1. Observe smoke capture
    • Is the hood in the correct overhang position?
    • Are there drafts along the cook line?
  1. Check for common comfort issues (hot/cold spots, entry doors that are hard to open, poor smoke capture, humidity, condensation dripping from diffusers and drafts).
  1. Inspect the equipment.
    • Are the filters clean?
    • Are the belts in good condition?
    • Are the exhaust fan wheels clean?
  1. Determine an intervention plan.
    • If some preventative maintenance actions and/or repairs need to happen, start with the service contractor.
    • If equipment is inoperable, have it repaired or replaced.
    1. If the preventative maintenance actions are in order and the problems persist, call in a certified air balance company that has experience with restaurants like yours.
Facility managers need to trust that their service contractors will notify them of airflow-related issues. Those technicians are out on the roofs and looking at the HVAC system components more than anyone else. If the restaurant has negative pressure or other out-of-tune symptoms, the service contractor needs to inform the facility manager right away. After all, you want your customers and employees to continue singing your praises. 
Air Balance in HVAC

Air Balance Basics for Existing Facilities

Posted on by Lindsey Burbee

We understand the concept of the “band-aid approach” whereby you find a quick cover-up to a problem without actually investigating the root of the it.  This concept applies frequently to Facility Managers or Building Owners wrestling with HVAC emergencies being caused by negative building pressure. They tackle issues such as condensation, hot/cold spots, humidity, odor, and difficult to open doors with “band-aids”. These “band-aids” are in the form of increased air conditioning, dehumidifiers, wet floor caution signs, door mechanisms, air fresheners, apologizing to patrons, comping customers’ bills, and so on.  This is understandable when you’re managing 80+ facilities, all with problems that stretch far beyond just HVAC.  However, it comes with a cost of spending a lot of time, money, energy, and reputation just to have the issues continuing to come back.  While balanced airflow is not a tangible product, the consequences of an unbalanced building are very perceptible.

Facility Managers are ready to de-mystify their HVAC issues by understanding the root causes.  Use the air balance basics below to recognize when an issue is airflow related.

What does it mean to have a balanced airflow?

Think of financial statements with income listed in one column and expenses in the other.  Much like a budget, you want incoming cash coming to be equal to or greater than cash going out. You typically want the air going into a building to be slightly greater than the air going out.  Similarly, think of a balanced scale.  In the graphic below, air is being drawn out of the building by exhaust fans at a rate of 4000 CFM (cubic feet per minute). This is to remove heat and smoke from kitchen cooking appliances and foul air from the restrooms. Air is also being introduced into the building through an outside air fan, at a rate of 4500 CFM. This is to provide fresh breathing air for the occupants and to replace the exhausted air.  The result is a slightly positive building pressure of 500 CFM (4500 – 4000 = 500), which signifies a balanced airflow.  Conversely, if air coming into the building is slightly less than the air leaving the building, then you have a negative building pressure, which is the frequent culprit of many HVAC problems.

Which brings us to a crucial pairing to the air balance concept.  That is if balanced airflow is peanut butter, then a performance test is the jelly.

What is an air test & balance service?
 

Air balance testing is the process of measuring HVAC airflow performance.  Once tested, the systems are then adjusted, or balanced, so the air brought into a building is slightly greater than the air being pulled out of the building.  The benefit for testing and balancing being a combined service is explained by Rob Falke, President of the National Comfort Institute, “This [positive] pressure condition can be designed, but to be sure it actually happens requires air diagnostic testing.  However, it’s hard to say how great the positive pressure reading in the building will be. It depends on how tight (or leaky) the envelope of the building is, and what other pressure generating forces exist, including the wind, appliances, exhaust fans, and the stack effect of the building.”  The result is a comfortable, healthy indoor environment with an HVAC system that is optimized to perform efficiently.

 Sources:

  • Digital image. Air Concepts LLC. N.p., n.d. Web.  Nov 25, 2015.
  • Falke, Rob. “How to Measure Building Pressures.” Contracting Business, 1 May 2006. Web. 25 Nov. 2015.