Tag: HVAC equipment and maintenance costs

Last Defense for IAQ – Clean Condensate Pans

By Tony Febbraro, Indoor Environmental Quality Consultant (Contributing Author to CRT)

Indoor air quality (IAQ) is directly affected by the building’s mechanical air conveyance system. The degrees of cleanliness of outdoor (fresh) air and recirculated (return) air will determine the amount of airborne and settled dust that enters the occupied space. The air conveyance system can be divided into two basic components: the Air handler unit (AHU) and the duct system. This article will address mechanical hygiene of the air handler unit and proper maintenance.

The primary components of the air handler unit are: filters, conditioning coils, condensate tray, blower assembly and internal insulation. Any of these will promote microbial growth and/or dust distribution.

The amount of moisture in the AHU will determine the environment conditions that promote mold and bacteria growth. These microbes may either be brought into the air conditioning system or will grow on unclean and damp or wetted surfaces in the air handler unit.

Dust contains a variety of materials. Outside source dust will contain mold, bacteria, pollen, silica (sand), biodetritus. Proper air handler hygiene maintenance is important for minimizing these pollutants.

The condensate tray provides the primary reservoir for microbial growth. Water collected here comes from condensed water off the cooling coils. This water has been wrung out of the air and collects any fine dust from the cooling coil fins. Over a short period of time, an untreated tray will accumulate enough fine ‘dust’ to cause two results: clumping of debris and microbial growth.

Clumping debris can a) clog the condensate tray and b) provide a food source for microbial growth. Even with very efficient filters, dusty will find their way into the air handler unit. Degraded internal insulation (fibrous glass or rubber) will release debris. In draw-thru systems, leaking or improperly sealed access doors will also allow unfiltered air into the blower chamber.

Clogged condensate trays will cause more moisture to accumulate on other surfaces including internal insulation and blower fan blades. This moisture will further collect ‘dust’ and promote microbial growth (amplification).

So it becomes apparent that a key component of the air handler unit is the condensate tray. It is the last defense of the AHU in providing acceptable indoor air quality.

Given the above, what do we look for in condensate tray hygiene?

  • Clumping or accumulation of dust/debris
  • Clogged condensate drain plug lines
  • Visible microbial growth

As air circulates through the AHU continuously, it is not likely that scheduled annual or semi-annual cleaning is sufficient to keep conditions acceptable. Treatment of the AHU needs to be on a continuous basis.

In our inspections across the country, it is easy to see the effects of poor hygienic maintenance. The common culprit is the condensate tray, often negating all the other ‘good’ conditions observed. Similarly, it is very easy to see the effects of a properly maintained system. Treated condensate trays have little to no accumulation of debris, microbial staining, corrosion or discoloration. These systems provide the best available indoor air quality.

Treatment limitations

Treatment systems come in many varieties. Some systems will focus on debris accumulation and are dispersants, usually some detergent. Others will focus on biocide abilities, ignoring the ability of molds and bacteria to ‘hide’ inside accumulated debris. Also note that what may kill bacteria can provide ineffective for molds. Some systems may work, but only for short periods of time as they are ‘spent’ with the first significant water condensation. In this case, you would prefer a slow time-release product to limit the amount of manual servicing or replacement.

Harmful to other components

Few people realize that certain chlorine-based treatment products, while effective against many microbes, may have adverse effects on rubber components including belts, seals and even rubber roof systems. Some products may have an extreme pH that can also affect (corrode) the metal tray.


Certain products will have distinctive ‘colors’. It is not unusual for certain table products to leave significant yellow stains both in the tray and all along the roof.

Optimum treatment

Proper hygienic maintenance of the condensate tray therefore requires that all conditions be addressed: clumping, biocide, pH, long lasting and aesthetics. While you may be able to purchase multiple products, the preferred products will have most or all of these features.

The main product observed in well maintained systems is Algae Guard by Controlled Release Technologies. After years of building inspections, this product has demonstrated itself as the most effective in addressing the four categories we described.

The product is used in main air handler units on both rooftops and mechanical rooms. The Algae Guard slow-release system contains detergents for dispersing debris, near-neutral pH to limit corrosion, and an EPS registered biocide that addresses both mold and bacteria and is non-odorous or staining.

Facility Environment Partners recommends this type of product often to maintain good AHU hygiene as well as bring less hygienic units up to acceptable levels.

See you next time on HVAC Preventive Solutions.

Tony Febbraro has been doing building studies since 1987 across the eastern United States. He is a Certified Indoor Air Quality Professional and president of Facility Environmental Partners, LLC, a consulting firm based in Florida.

Case In Point: Associate with Associations

In my last blog, Case In Point: How Vendors Strengthen Our Business, I talked about how vendors play an integral part in a business’s success. Associations can also be a valuable, yet often overlooked, resource for strengthening business success. Here is how CRT’s relationship with NADCA National Air Duct Cleaners Association has grown over the years to the benefit of both parties.

When the recession hit a few years ago, budgets for HVAC maintenance, including air duct cleaning, seemed to be one of the “luxuries” many building operators had to cut. Thinking quickly, NADCA made air handler restoration a major focus, which gave members an opportunity to provide a much needed service to their clients. Members were given training, in both classroom and hands on sessions, showing the ease of restoration when compared to replacement.

NADCA members worked together to share sales tips, application tips, success stories and horror stories from these new ventures. Each year at the annual exposition, knowledge in the area of restoration seemed to grow. Groups of members would hang around our booth and share stories about jobs involving our Pancrete products. Just this past March, when NADCA held their annual show in Puerto Rico, members told us about how they have grown their business and saved their clients money by applying Pancrete.

Our relationship with the NADCA organization has also strengthened our relationship with individual members. This has created new and additional opportunities for everyone involved. If you have a story to tell about how being part of an association has effected your business, I’d love to hear about it. Please write your story in the comment section below.

Rachelle Tinley is the assistant executive director of Controlled Release Technologies, Inc., a research, development and manufacturing firm based in Shelby, North Carolina.  CRT is an IFMA CSP, an EnergyStar Partner and manufacturer of independently-certified Green products for HVAC maintenance. Since 1986, CRT has been creating leading edge HVAC maintenance products that have become industry standards, used in thousands of commercial buildings world-wide. CRT employees are members of BOMA, ASHRAE, ASHE and the American Chemical Society. www.cleanac.com

Technical Corner: Indoor Environment Connections

Recently I was asked to write an article about HVAC System Hygiene for the March issue of Indoor Environment Connections. In this article I discussed four specific, and frustrating situations I have come across during my 25+ years in the industry. These include outsourcing by a major Southeast resort, coil cleaning at a hotel, inspecting an air handler serving a pediatric ward, and ignoring obvious problems at a separate major hospital. To read these field cases, please visit or download http://www.ieconnections.com/pdfs/newsletter/2012/IEC-03-2012.pdf and scroll to page 24.

As always, I welcome your comments below.

Lynn Burkhart is the founder and president of Controlled Release Technologies, Inc. located in Shelby, North Carolina. More information about the company, and its products, can be found at http://www.cleanac.com and by calling (800) 766-9057.

Technical Corner: Is Bigger Really Better? (Part 2)

Those who have read Part 1 of “Is Bigger Really Better” know that when it comes to air conditioner sizing, bigger is not necessarily better. But there are areas where bigger is better when it comes to preventative maintenance.Take the area of the condensate collection pan for example. Collection pans get dirty and produce odors. In some cases they are a breeding ground for bacteria, fungus, and other microbes.There is no question that these areas are among the dirtiest, if not the most offensive, areas of the air handler. Water overflowing comes about from fouling so bad that the collection pan drain line becomes solidly plugged, preventing water from flowing out naturally.Before the mid-1980s, all that could be done was to add tablets to the condensate pan to attempt to address the problem. Tablets dissolved quickly. Even those that purported not to dissolve quickly (a small weighted red box), an analysis of the active ingredient showed its’ solubility rate was 1.5 grams per liter of water. This would be how much would dissolve in one liter (about a quart) of water.

These type products, considered the best at the time, were used with varying results. It was not uncommon to see literally dozens of these boxes in an air handler, all with fungi and other microbes growing around them.

If the products were that good and they were not consistent, then there must be something we didn’t know as to why. One reason might have been that the water flow was much higher than the tablet could effectively treat. We checked a small fan-coil unit in Florida and found that this smaller unit flowed 1-1⁄2 gallons of water per day or about 6 liters of water.

Now if 1.5 grams of the tablet dissolved in 1 liter of water, then 6 liters would take up 9 grams with one day’s flow of water. But the tablets weighed 3⁄4 ounce or 21 grams. At its 50% active ingredient level, that meant the tablet contained only 10.5 grams of actives. So, in a little over a day, there would be nothing there to work with.

Most engineers and professionals need products they can rely upon, and HVAC maintenance people demand the same. It is irritating to have to make an emergency call to a unit to handle an overflow, or having complaints on odors, and other service related matters.

In 1986 our company made a major breakthrough in this area. This was the development of the first true controlled-release condensate pan treatment. Unlike old treatments used without consistent results for decades, PanGuard and Algae Guard makes a remarkable leap forward. They slowly release ingredients over a 3 to 6 months period of time. This lays on the table what every manager wants: consistency and predictability of results.

Time after time, it works. No surprises and no extra labor. In fact, since the products are only placed in the condensate pan when filters are changed, there is no extra work involved.

To obtain this optimum performance, we determined the condensate flow of water from each tonnage of air conditioning unit. Next we oversized Algae Guard and PanGuard to insure that no matter what conditions would occur, the products always work.

Because upsets seem to occur when one least expects them, we went that extra step by being conservative in our controlled release products: they were engineered to handle all the water from a certain tonnage of air conditioner when that unit was running 24 hours per day, 7 days per week, at a relative humidity of 100%. No other manufacturer of condensate collection treatment products engineers a product to these high standards. With these products, failure is not an option!

Our EPA registered Algae Guard product contains 32% active ingredients as shown on its box label. Users are encouraged to check our box label with other timed-released products to see the difference quality engineering makes.

There is only one other polymer-based product on the market similar to ours; it uses our old 1986 polymer matrix.

Good, but in 2007 after years of further research and development, we upgraded our system by synthesizing a brand new timed-released molecule that is much sturdier, and more efficient at the controlled release of working ingredients. This coupled with our 32% active ingredients in the case of Algae Guard increases its desirability over a 20% active, lower performance polymer molecule.

In this case, bigger is better. Upgrading our products continuously insures our customers only get the latest in technology as we develop it.

CRT Time Released Products

Lynn Burkhart is the founder and president of Controlled Release Technologies, Inc. located in Shelby, North Carolina. More information about the company, and its products, can be found at http://www.cleanac.com and by calling (800) 766-9057.

Technical Corner: Is Bigger Really Better? Pt.1

When it comes to many things air conditioning systems, bigger is not always better. Take the sizing of an air handler for instance.

Many instances have been uncovered where architects and mechanical engineering firms oversized the air handler. For example, where the conditions called for a 50 ton unit, 75 tons or higher was installed. Bigger must be better was the supposed reasoning.

Unfortunately, this mistake costs the building owners over 20 million dollars in the end and nationwide infamy. Why?

Air handlers not only must provide adequate cooling, but also reduce the amount of moisture or humidity of the inside air. When the units were started up, cooling was almost immediate. However, the cooling capacity of the units was so large that the unit was able to come on only for a few minutes before it shut off again.

As a result, little moisture was removed and the humidity levels remained high. In Florida, where high humidity is a fact of everyday life, moisture removal is vital. Normally in air conditioners where the air moisture condenses upon cooling coils (similar to the condensation on the outside of a glass of water you may drink in a restaurant), and moisture in the air is removed.

What is known by all indoor air quality professionals is that humidity levels over 60% are conducive to fungal (mold) growth. In this Florida case above, moisture was not removed ever from the air. A building occupant, after the new building was condemned and occupants evacuated, stated “It was either hot and damp or cold and damp in the building. But it was always damp.”

Owners were confronted with bulldozing down the marble enclosed building and re-­‐building it from scratch, or trying to repair the existing building.

There are other areas however where bigger is better. Handling mold issues in the HVAC condensate collection pan is one of them. My next blog will address this important factor.

Please do not hesitate to leave your comments or testimonials below.

Lynn Burkhart is the founder and president of Controlled Release Technologies, Inc. located in Shelby, North Carolina. More information about the company, and its products, can be found at http://www.cleanac.com and by calling (800) 766-9057.