Tag: tab contractor

Top 3 Points to Consider Before Scheduling a Balance

Posted on by Lindsey Burbee
  • HVAC equipment is installed and operational.

This one seems like a no-brainer, but there are always occurrences when Melink arrives to perform a balance and necessary equipment either hasn’t been installed or isn’t properly operational. Examples might 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 that Melink 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.

  • All HVAC equipment can be easily accessed.

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 that must be considered.

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.

  • 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 service with Melink approximately 2-3 weeks out from turnover will help to ensure a proper and complete balance, and enough time to work through any punch-list items or lingering comfort issues for the customer.

Want to learn more? Contact us today!

A Good Time For Technology

Posted on by Lindsey Burbee

Future of Technology

“Life moves pretty fast.  If you don’t stop and look around every once in a while, you could miss it.”  In my estimation, this quote from Ferris Bueller is more relevant now than when first uttered.  We’re in a period where everything continues to speed up. We’re moving along at breakneck speed to get to the next task, the next meeting, the next event, that it’s often easier to keep your head down.  The downside is that it’s easy to miss some of the amazing things happening in the world due to technology.

Smartphones

Smartphones, for example.  In the span of just a few years they’ve managed to become a nearly indispensable tool.  Gone are the days of proud parents stuffing their wallets with photos – you now have a literal gallery at your beck and call.  Simply carrying the phone gives us the ability to capture those special moments that in years past may be missed.  Try remembering what life was like travelling to a new city before we started carrying portable GPS units in our pockets.  What would previously take hours of planning is now done in minutes (if not seconds).  That’s not to say the consequences of ‘pocket computers’ have been beneficial, but I’d argue the good outweighs the bad by a significant margin.

Furthering Technology

Imagine opportunities to create new technology.  Instead of further connecting people (like the smartphone did), think of developing the next generation of sustainability.  Advancing business capabilities to reduce the amount of energy they consume and to make facilities healthier.  To help build intelligence that create win-win scenarios for companies and consumers at the same time.   Regardless of anyone’s beliefs on climate change and why it’s happening, it’s clear that the climate is changing.  Another thing that has been clear for some time is that the resources that we have on this planet are finite.  Finally, we’ve also learned that the cheapest energy of all is the energy that doesn’t get used.

Make an Impact

Right now, there is such an opportunity available.  Melink is actively searching for an Embedded Software Engineer and an Application Developer who would like to join our family as we continue our journey towards a brighter, more sustainable tomorrow.  We’re growing our sustainable offerings. These offerings include energy-saving demand controls for commercial kitchens (Intelli-Hood), innovative geothermal solutions (Manifest), and HVAC commissioning (Test and Balance). Melink is about to release an innovative new building health monitor (PositiV) and has more innovation on the way.  We’re also creating an awesome Portal that will connect our employees, technology, products, and customers with a clean, intuitive interface. This will create new applications to expand the reach of our hardware and improve the work-life balance of our employees.  Help us build the new tomorrow.

Apply online here

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.

What to know about choosing an air balance contractor

Posted on by Lindsey Burbee

Due to the skill level required and equipment needed, facility managers and mechanical contractors hire professional test and balance contractors to bring buildings into balance at the end of construction, remodels, rebalances for existing buildings and equipment changes. When HVAC equipment is installed and started up, it may not function according to design specification and eventually will delineate from proper operation if not corrected. 

Facility managers and mechanical contractors also bring in TAB contractors to investigate HVAC comfort problems. Are you aware that most HVAC problems stem from poorly maintained HVAC equipment or performance assumptions?

Selecting a balancing firm can be tricky business, but it doesn’t need to be. Following are criteria for choosing a balancing contractor, based on our experience during the past 30 years. We hope our perspective will serve you.

  • Use a certified firm
  • There are two main certification organizations:
  • Look for thoroughness. Like any service, you want to be sure your vendor is concerned about the details.
  • Look for integrity. Since most of the value of an air balance is invisible, you need a vendor you can trust.
  • Experience with your industry. HVAC systems differ among restaurants, retail stores, hotels and hospitals. Make sure your balancing partner is familiar with your type of facility needs.
  • Maintain objectivity. Have a third party firm balance your HVAC system to prevent shortcuts and misreporting.
  • Hire directly. Avoid conflicts of interest by hiring the balance partner yourself.
 Air balance report necessities
  1. Air flow measurements and adjustments
  2. Punch list with images
  • Punch list items refer to discrepancies with the design prints. For example, the prints might show there is a diffuser in the rest room, but the facility does not have it.
  • HVAC equipment data
    • Make, model, serial number, fan/motor data, voltage, belt size, equipment condition, amperage, pulley size, etc.
  • Building pressurization
    • Reading of the balanced building pressure

The above list includes the basic deliverables you should expect from an air balance report. You can read our article  How to read a Melink Test & Balance Report for a visual example of an air balance report.

To prepare for the service, a balancing firm will request the design prints of the facility and inspect any previous balance reports. In many cases with existing buildings, prints and reports are unavailable. If that happens, the air balance technician will have to work from best practice measurements. This is one of many situations where having an experienced and certified balancer is an asset because of the knowledge required to do this well.

Once onsite, the balance technician will briefly talk to your management staff and ask about any HVAC-related issues they are experiencing. A common complaint of restaurant facilities is a hot kitchen, which can be indicative of a rooftop unit with dirty blower wheels or filters, as well as loose belts on a failed compressor. These complaints give the balance technician an idea of where to begin.

Next, the balancer will spend time inspecting and measuring the equipment on the roof. He or she will record RPMs and amps, check exhaust fans and look for basic adjustments. Then the balancer will go back inside to check building pressure and take measurements of the airflow. All of this data will tell the technician what he or she needs to do. After more adjusting, such as dampers or RTU belt tightness, and measuring the effects, the technician will bring the HVAC ecosystem back to design standard.

At that point, pressures and measurements are then documented in a report. In the case of a Melink balance, the technician will also check thermostats and train staff on the proper settings, if requested by the manager. Findings will be explained to the manager as well. Finally, the facility manager or project manager will receive the report after it has gone through quality inspection.

ADDITIONAL READING:
Sources:
  • DuChane, Greg. “Optimizing Air Balance Report Data.” Trane Tracks (Apr.2015): n. pag. Trane. Web.
  • “NEBB.” International Certification, High Performance Building Systems. N.p., n.d. Web. Sept.1, 2015.
  • Prager, Ron. “Demystifying HVAC: Why Test and Balance?” (n.d.): n. pag. Web. Sept. 1, 2015. 

Troubleshooting Air Balance With Mechanical Contractors

Posted on by Lindsey Burbee

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. .