Category: Science & Energy

When is a good time to clean coils?

Over the years our company has been asked about best practices for cleaning coils.

  • When should coils be cleaned?
  • How to tell if the coils were properly cleaned?

This is the first in a short series of blogs that addresses these issues.

A primary variable that determines ones coil needs to be cleaned is the pressure drop across the coil itself. Usually, higher pressure drops are indicative of a coil that is fouled with dirt and/or organic growth.

IPK Photo Application
Dirty Cooling Coil 

Sometimes the coils appear visibly dirty, this in itself might be reason to go through a coil cleaning. Another factor is that the AC unit doesn’t cool as it should.

For example, a brand new through-the-wall AC unit, such as found in many hotels, might take 3/4 hour to drop the room temperature 8 degrees. The same unit with a dirty coil might take several hours to cool the same room. One major drawback is the unit is running several times longer to do the same work. Occupants can be dissatisfied with the slow cooling. In my own experience, I actually left my hotel room because it took several hours for the temperature to go down.

As mentioned, the unit works strenuously when it is dirty. This increased usage of power raises the electrical costs monthly. All this unnecessary work & money out of your pocket, when you have a solution as simple as cleaning the coil.

Over the past decades, we all have intuitively known that dirty coils drive energy costs up, but few know how much or if it was of any true financial consequence. Since up to 50% of a buildings electrical usage is consumed by the HVAC system, it would be good to know from actual studies how dirty coils affect your bottom line. Is it substantial or not?

Fortunately, the ASHRAE society did a complete engineering study specifically on this matter & published it in their journal.

While the results are not surprising, the affect on your bottom line is. If you do not have the article, feel free to contact us.

Drop us a line with comments, questions, suggestions, feedback on what you do with your coil. Any experiences you can comment with?

Lynn Burkhart – President of Controlled Release Technologies 


Contact us: – 800-766-9057 –



National Geographic: 5 AC Designs Inspired by Nature

More often than not, my favorite response to every question is, “I’ll Google It” or “I can Google faster than you”. Very often I run across a word that I’ve never heard before and have to google the definition.

This week I discovered the word:


  1. the design and production of materials, structures, and systems that are modeled on biological entities and processes.

I ran across this word in an article by National Geographic. National Geographic stated, “Designers are turning to biomimicry to develop better cooling technologies. Air Conditioning uses a tremendous amount of energy, but a new group of designers think they can solve that problem by mimicking Mother Nature’s craftiness.” 

Who knew that Nature & Air Conditioning had so much in common.

“These designs suggest some of what could be learned by applying the lessons of biomimicry to the problem of air-conditioning in particular.”

Fire passes over a termite mound. Here is an image of termite mounds that have survived the worst of blistering hot conditions. Thanks to google I found termites have had quite the influence over our ventilation, heating, & cooling.

Many species of termites in the world live in termite mounds. These termite mounds are made up of soil, mud, chewed wood, saliva, and feces. Oddly enough, the combination make the mounds super strong & even fire resistant. The mound will consist of “chimneys” that allow warm air inside the mound to vent upward and outward. Apparently, termites are quite smart. They open and close a series of vents throughout their mound to allow airflow and circulation, keeping the mound from overheating.

Any of this sound familiar? How amazing that these annoying creatures have inspired our ventilation!

About us

“The CRT Tipster” is an HVAC tips and news blog owned by Controlled Release Technologies, Inc. We are a chemical manufacturing company in Shelby, NC, that creates products for HVAC maintenance and more! Find us at, or call us toll free at 800-766-9057.


3 Reasons to Optimize Your HVAC Equipment

3 Reasons to Optimize Your HVAC Equipment

Homeowners have good reason to want to get the most heating and cooling out of their HVAC equipment: these systems account for up to 48 percent of a typical household’s utility bills, notes the U.S. Department of Energy (DOE). However, the benefit of properly maintaining an HVAC unit or upgrading to a high efficiency model isn’t only financial—though that’s certainly a big one. Following are the 3 top reasons to optimize your HVAC.

3. Sustainability: Another big incentive to optimize your HVAC equipment is the environment. The less electricity your home consumes, the lower your household’s carbon footprint. The government offers further cost savings in the form of tax credits to encourage homeowners to reduce energy dependency by boosting efficiency. These tax credits are a way for homeowners to save money while also feeling good about the decisions they’re making for their families and communities. 

2. Convenience: New or properly maintained HVAC equipment doesn’t just save money; it also makes a homeowner’s life easier, as unexpected breakdowns—and the uncomfortable indoor climates that accompany them—are less common.

1. Savings: The Environmental Protection Agency (EPA) asserts that an average homeowner can save as much as $750 every year by opting for an Energy Star HVAC system. However, homeowners do not need to replace their existing equipment to boost efficiency and save. Regular maintenance can help too. Below is an infographic The Refrigeration School developed that is a great source of information on DIY and professional HVAC maintenance.

HVAC Optimization Help

Whether your HVAC equipment is newer or older, maintenance is key to improving efficiency and extending its lifetime. Check out the infographic below and navigate around the website for tips and products that can help you optimize your HVAC system.


Huge thanks to Kathy Jackson with The Refrigeration School for this Guest blog.

About us

“The CRT Tipster” is an HVAC tips and news blog owned by Controlled Release Technologies, Inc. We are a chemical manufacturing company in Shelby, NC, that creates products for HVAC maintenance and more! Find us at, or call us toll free at 800-766-9057.

Super Cool Time-Lapse Video: Building a Wind Turbine

We love cool science and energy stories here at CRT. Recently, our president came across this time-lapse video from MidAmerican Energy on their recent construction of a wind turbine. You’ll be amazed by the size, scope and sheer numbers of wind turbine construction! Check it out.