How Restaurants Can Verify Proper Ventilation for Health & Comfort

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.

TOP 3 Points to Consider Before Scheduling an HVAC Balance

There are a few important items that you want to take into account before you schedule an HVAC balance. While these 3 points may seem obvious, there are many instances where a technician gets onsite and the job-site isn’t ready or they can’t access areas that they need. These tips can save time and money for everyone!

1. HVAC equipment is installed and operational.

This one seems like a no-brainer! However, there are always occurrences when a technician arrives onsite to perform a balance and necessary equipment either hasn’t been installed or isn’t properly operational. Examples include VAV’s or dampers that haven’t been installed, or a RTU that isn’t operational.

Ensuring that all ductwork has been completed, balancing dampers are properly installed, any grilles, registers and diffusers are installed, and the RTUs have clean filters helps make sure a technician can provide a proper air balance, as well as mitigate any potential return service costs. Making sure that all equipment (especially RTUs) has undergone a proper start-up to confirm power should always be completed ahead of Melink’s arrival.

2. All HVAC equipment can be easily accessed by a technician.

Another hindrance to any proper test & balance is not being able to access the necessary equipment. This includes equipment installed inside the building, as well as equipment on the roof. When working with a customer located inside a mall or shopping center, security and approved roof access becomes another added component.

Melink typically requires assured access to all applicable HVAC system equipment, including RTUs, VAVs, Exhaust Fans, dampers, etc. Access to fully open dampers, ceiling-height diffusers, and thermostats that may be in an office is necessary to properly complete the balance. Our Account Coordinators will also discuss roof access, security measures, and accessibility to ladders or lifts.

3. Allotting adequate time (2-3 weeks) to schedule and complete the balance.

Though some seasons are busier (or slower) than others, our goal at Melink is to provide every customer the same level of service excellence no matter the time of year. This includes communication with the customer, scheduling the site visit with one of our National Network technicians, performing the balance and working with the customer on any punch-list items, and finally, providing a certified test & balance report.

Our team of National Account representatives and technicians work with the customer through each step of the process. Scheduling an HVAC balance with Melink approximately 2-3 weeks out from turnover will help to ensure a proper and complete balance. It also allows enough time to work through any punch-list items or lingering comfort issues for the customer.

Study Finds Building Mold Can Become Airborne, Highlighting Need for HVAC Test and Balance Services

A recent study by The National Veterinary School of Toulouse in France revealed that mycotoxins can be inhaled and should be investigated as parameters of indoor air quality. This means that food fungus formerly thought to have no effect on air quality can actually become airborne and dangerous to building occupants. The results were published in Applied and Environmental Microbiology, which is the American Society for Microbiology’s journal.

 

The researchers were interested in the fact that far less research exists on the dangers of airborne fungal toxins compared to fungal toxins in foods. The research team focused on three fungi commonly found in contaminated food: Penicillium brevicompactum, Aspergillus versicolor and Stachybortys chartarum. The research team conducted this study by creating a flowing stream of air over a piece of wallpaper contaminated with the three fungi and then analyzing the samples of air.

 

The results showed some toxins from the contaminated wallpaper were present on tiny particles of dust that were considered to be easily inhalable. If you own a restaurant, hotel, retail location or supermarket, these results should be eye-opening. These findings should amplify the importance of performing regularly scheduled HVAC test and balance services to ensure your HVAC system is operating as designed, and not contributing to organic growth.

 

As a business owner, it’s extremely important to make sure that your building’s HVAC system is working properly, not only for health reasons like the airborne fungus we specified above, but for first impressions of new customers. An unbalanced HVAC system may cause humidity problems, and this may result in fogged over windows in the morning, which prevents customers from being able to see inside. Poor air pressure can even make it difficult to open doors.

 

An unbalanced HVAC system can also result in uncomfortable temperatures and humidity that does damage to ceiling tiles and creates slippery floors which can become both a safety issue and legal liability. In kitchen environments, an unbalanced HVAC system can also cause smoke and odors to flow past the hood and  seep into the dining area.

 

Here at Melink we provide HVAC test and balance services, HVAC commissioning, indoor air quality tests and water balancing services that will help to alert you to dangerous conditions within your building.

 

 

 

Our 100 percent self-performing network of technicians ensure consistency across your locations. Mechanical systems fall out of alignment over time, you should keep your HVAC at peak performance by rebalancing it every three to five years. We also offer comfort investigations that can be conducted after HVAC complaints or negative building pressure issues.

 

Many of the largest chains in the US recommend Melink because of the convenience, consistency and cost effectiveness of our service. They also know that our reputation for integrity, quality and service is proven. As we’ve demonstrated, not only can overlooking the air quality of your building be dangerous for the health of the building’s occupants, but it can also cause a business owner to lose customers. In order to best help business owners decide if it may be time for an HVAC Test and Balance service, we’ve provided these questions to ask yourself:

 

Is there a draft at the front door of my building?

Is there leakage from units in the ceiling?

Is there condensation dripping from diffusers?

Are there noticeable hot and cold spots?

 

If you answered yes to any of these question, you are likely due for some servicing. Reach out to us today to improve the conditions of your building and increase the quality of your business!

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

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 a lot like a piano being out of tune. In addition to unhappy customers and employees, these comfort issues typically are indicators of energy inefficiency within a system. 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

7 Steps to HVAC Balance

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 T&B 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.”

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. 

Troubleshooting Air Balance With Mechanical Contractors

Are you still experiencing HVAC comfort or efficiency problems?  It’s time for the next level of technical HVAC skill.  Though at this point you may have realized you’re dealing with negative building pressure, you might wait on calling the air balance contractor and first become more informed about the problem with your management team.  It’s time to call in your trusted mechanical contractor (MC).

Your contractor’s first steps will be to inspect many of the same areas we advised in our previous post. These areas should include circuit breakers, thermostats, as well as the areas listed below.  In addition, you should locate any past air balance reports and confirm that all the punch list items were corrected.  With these observations and baseline data as your starting point, you or your MC can begin to formulate a hypothesis. To dig deeper into problems, check the following areas where we most frequently find the causes of HVAC comfort issues:

1.   Filters inside the unit

Dirty, old, or clogged filters will restrict airflow through the unit.  Filters should be at least replaced quarterly for a commercial unit and can be added as part of a preventative maintenance scope of work.  In the Restaurant Facility Management Association’s Facilitator Magazine, Red Lobster Facility Manager Angela Hughes writes in her article Staying On Top of Comfort Concerns, “The washable metal filters inside each makeup air fan need to be cleaned during major preventative maintenance.  These are often overlooked by HVAC preventative maintenance vendors.  Dirty filters can block airflow into the unit and greatly affect the building balance.  If the filters are damaged or missing, be sure to replace them.”

Dirty air filters

Above: Dirty Outdoor Filters

 

2.  Inspect coils inside units

Dirty, clogged, or frozen coils can also heavily restrict airflow through the unit. Mechanical contractors are equipped to unfreeze and clean coils.  Angela Hughes explains, “Dirty coils will cause the unit to freeze up and temporarily shut down, which causes stress on the compressors.”  Further, if the rooftop unit (RTU) blower compartment and/or coils are dirty, then they are likely causing reduced airflow and contaminated air.  The solution is to clean internal components of the RTU.

Frozen evaporator coil
 

Above: Frozen Evaporator Coil

Dirty RTU blower compartment

Above: Dirty Rooftop Unit Blower Compartment
 

RTU dirty coil

Above: Dirty blower wheel inside Rooftop Unit

3.   Check refrigerant levels

Low refrigerant levels can lead to uncomfortably warm temperatures. Your mechanical contractor should be equipped to refill refrigerant.

 

4.   Open up units and inspect outside air dampers

The amount of outside air is specified in the building’s design, however it is often adjusted later as a quick-fix for short term issues, leading to bigger problems in the long run.  It is common to find improperly installed and inoperable outdoor air dampers, which negatively impact the building pressure.   The dampers will need to be adjusted to proper position and outside air intakes may also need to be installed to achieve desired airflow.

Improperly installed air dampers
 

Above: Improperly Installed Outside Air Dampers (sealed closed with caulk)

 

5.   Check for negative building pressure in your facility

The tell-tale sign of negative building pressure can be found with using the door test.  A quick way of checking your building’s air pressure is to test it with a lighter or a match at an exterior door.  Crack the door open and place a lighter in the crack as pictured below.  If the flame pulls toward the inside of building, then the building is negative.

Door lighter test

 

Above: If flame pulls toward inside of building, the building is negative.

 

6.  Has your facility undergone a remodel, renovation, or a major change in equipment?

Remodels, renovations, or major equipment replacements change the distribution of airflow and requires an air balance service.  HVAC equipment installed in a building will not function at design specification at start up.  Adjusting the system to design specification requires testing, adjusting, and balancing.

These are 6 examples of what your mechanical contractor may discover in their assessment process.  If they are able to find and properly resolve the HVAC comfort or efficiency issues, then your troubleshooting may end here.  If not, you may need to consider calling in a certified test and balancing firm.  See our next post in this series for understanding what to look for in a test & balance contractor.

Additional Reading:

  1. Bringing in an Air Balance Contractor, Larry Moore, Melink Test & Balance
  2. Angela Hughes, a Red Lobster Facilities Manager with distinguished technical knowledge of HVAC systems, authored a very practical approach for FMs to self-diagnose comfort problems without prematurely spending money on contractors. Staying On Top Of Comfort Concerns
  3. For suggestions on preparing for an air balance, read Optimizing Air Balance Report Data  by Greg DuChane, Retail-Restaurant Vertical Market Director at Trane
Resources:

DuChane, Greg. “Optimizing Air Balance Report Data.” Trane Tracks (Apr. 2015): n. pag. Trane. Web.

Hughes, Angela. “Staying On Top Of Comfort Concerns.” Facilitator Magazine Apr/May (2015): 66. Restaurant Facilities Management Association, 25 June 2015. Web. 26 Aug. 2015.

Melink Test & Balance Technicians. HVAC Deficiency Images. Digital image.Melink Test & Balance. Melink Corporation, n.d. Web. 26 Aug. 2015. .