Tag: airflow

How Restaurants Can Verify Proper Ventilation for Health & Comfort

Posted on by Lindsey Burbee

If you have owned or operated a restaurant, you are familiar with the challenges of maintaining proper airflow throughout the building. From the kitchen to the front of the house to the back of the house, proper airflow can be challenging to keep in balance. That said, restaurants go out of balance for many reasons, wreaking havoc on a building’s health, comfort, and ventilation.

Does your restaurant look like this?

 

Restaurant Ventilation Problems

Unfortunately, these types of issues are extremely common in existing restaurants throughout the United States, and, when left unaddressed, can lead to negative building pressure, which causes serious long-term damage, poor indoor air quality, poor energy efficiency and uncomfortable conditions.

 

 

What are the industry guidelines for building ventilation?

ASHRAE 62.1 outlines minimum ventilation rates for various types of buildings, as well as other measures to ensure acceptable indoor air quality (IAQ) for human occupants.  In a nutshell, ASHRAE recommends a certain minimum amount of fresh outside air be introduced through the building’s HVAC system.  It also recommends that the proper amount of outside air be verified at least every five years. Without properly setting the outside air intake volume, buildings can experience negative building pressure and exhibit sick building characteristic. The best way to verify outside air is to hire a certified Test & Balance company, such as Melink, which has the proper air measurement instrumentation and years of experience.

 

 

How can I tell if my restaurant is properly ventilated?

 

  1. Observe restaurant conditions and ask staff for a log of comfort issues
  2. Turn on HVAC equipment, “Fan On” mode
  3. Check the front door for signs of negative building pressure
  4. Observe the kitchen hoods for proper smoke capture
  5. Check the restaurant for drafts
  6. Inspect the rooftop equipment to ensure it is in working condition
  7. Ensure your HVAC preventative maintenance services are being performed satisfactorily
  8. Contact Melink for building balance and comfort investigation services

 

 

How can I be sure my building stays healthy, comfortable, and properly ventilated for the long-run?

More and more restaurant chains are interested in the idea of “ongoing commissioning.”  With scant facilities budgets and facilities managers stretched ever thinner, it is not feasible to routinely send someone to each facility to verify building health, ventilation, and comfort. Out of this necessity, Melink’s PositiV® Building Health Monitor was born. PositiV is a standalone system that monitors your building’s pressure and remotely tracks building health. Alerts are sent when the system detects anything is out of set parameters. Moreover, PositiV monitors temperature, relative humidity and CO2 so that you gain a full picture of the health of your facility.

 

 

Melink PositiV Building Health Monitor

 

PositiV is THE solution toward being able to actively monitor restaurant health, comfort and ventilation for the long-haul, and it is the most affordable way for multi-site facility managers to proactively stay ahead of building health issues before they become big facility problems.

Below is a REAL restaurant’s PositiV data. The site is taking action to improve negative pressure and building ventilation issues before they cause building damage, mold and comfort problems.

 

 

Restaurant Ventilation Case Study Example

 

 

Ensure Your Restaurant’s Ventilation & Air Quality

For further information restaurant ventilation and PositiV (ongoing commissioning), please e-mail [email protected] or call us at 513.965.7300.

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.

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.

The #1 Air Balance Bummer: Negative Building Pressure

Posted on by Lindsey Burbee

What’s the first thing you experience when you arrive at a restaurant? You might say the delicious aromas, lighting, and possibly the smiling hostess asking how many are in your party. But the very first thing anyone experiences is the door. How many times have you found yourself struggling to open the darned restaurant door? You pull the handle, but it won’t budge. You try the other handle, to no avail. You think, “There’s no way this is locked, it’s the middle of the lunch rush and I can see people inside.” With all your strength, you finally crack it open and squeeze through. You might feel a large draft on your back and then, finally, slam! Woman pulling on door

 If this common door problem has happened to you, how many times do you think it has happened to customers entering one of your restaurants? While your first hypothesis may be that it is a door hinge problem, it is actually part of a larger problem: negative building pressure. And that is just one symptom of a sick building.

Sick Building Syndrome is a serious situation restaurant facility managers and owners cannot afford to take lightly.

Check out these three must-know tips:

  1. Know what to look for. This simple illustration shows the most common problems related to HVAC air balance, which cause sick building syndrome.  Educate your teams as well.

Unbalanced HVAC system problem graphic

  1. Assign someone at each restaurant location – the store manager or maybe a shift leader – to watch for these sick building symptoms. Give them a process for reporting these problems so you have a record of the issues.  View our Sick Building Syndrome white paper and distribute to your teams for diagnosing comfort problems.
  1. Don’t just take it from us, read more on this important topic from expert Rob Falke, How to Measure Building Pressures, published on ContractingBusiness.com, an online industry publication.