“I was told that the average life expectancy of an A/C System is only seven to ten years. How can this be? My System up north is twenty years old!” While split air conditioning systems in northern areas of the country may have a longer lifespan in years, generally speaking, the actual run-time over a […]
“I was told that the average life expectancy of an A/C System is only seven to ten years. How can this be? My System up north is twenty years old!”
While split air conditioning systems in northern areas of the country may have a longer lifespan in years, generally speaking, the actual run-time over a lifetime, in hours, is about the same. Of course, it will also make a difference if you’re comparing a location close to salt water, or to marshy areas, to that of an arid climate.
Here in southwest Florida, we’re both close to salt water and marshy areas. Additionally, we’re typically in peak cooling season for about 3-4 months and in just-under-peak conditions for another 5-6 months. This results in our cooling season lasting roughly 9-10 months. In addition to extended periods of high temperatures, our climate is also very humid (dry air cools far more quickly than moist air). All of these factors result in an average of 2,800 run-hours per year! In a typical year, it would be the equivalent of a 53+ hour work week, every week, or like putting over 100,000 miles on your car in a year! It’s hands-down, the most used, hardest working, appliance in your home.
Another factor that comes into play with lifespan is the continually changing regulations for increased efficiency of split air conditioning systems. A split system consists of an air handler inside (its primary components being the evaporator coil and blower motor) and an outdoor condensing unit (with its primary components being the condensing coil, compressor, and fan motor).
These two units, air handler and condenser, must be rated as a certified “match” per the Air Conditioning, Heating, and Refrigeration Institute (AHRI). Therefore, depending upon the age of the system, type of refrigerant it utilizes, and the efficiency rating (SEER, or EER); if the air handler or condensing unit suffers a major component failure (coil or compressor), it may not be possible to replace only that portion of the system (due to lack of a rated match). In these instances, the cost to replace the entire system is frequently a more economical choice than that of a very costly repair.
Meeting the higher efficiency ratings is achieved, in part, by being able to transfer heat faster (in less run-time hours). Thinner coils (than in older units) result in a more efficient exchange of heat. While this may result in the coils being more susceptible to wear and environmental corrosion, the decreased operating costs of new systems outweigh the expense of replacing an old system sooner, rather than later. According to FPL’s annual cooling cost comparison chart, the annual cost of operating a 3.0 Ton, 10-SEER system (typical of the 1990’s) is $1,009; whereas a current 20-SEER system is estimated to cost just $500 per year to operate. Based on those figures, over the course of ten years, the 10-SEER system would cost $5,090 more to operate.
AHRI: Air Conditioning, Heating and Refrigerant Institute
SEER: Seasonal Energy Efficiency Ratio (peak season; higher ratios indicate increased efficiency)
EER: Energy Efficiency Ratio (overall; higher ratios indicate increased efficiency)
“My system is brand new and has a 10 year parts warranty, so why would I purchase another warranty?” It’s important to realize that manufacturer’s parts warranties provide only the replacement part. They do not cover labor, refrigerant, processing, and shipping fees or any incidental items necessary in completing the repair. The customer will be […]
“My system is brand new and has a 10 year parts warranty, so why would I purchase another warranty?”
It’s important to realize that manufacturer’s parts warranties provide only the replacement part. They do not cover labor, refrigerant, processing, and shipping fees or any incidental items necessary in completing the repair. The customer will be responsible for all expenses, other than the part itself.
For example, the cost to replace an evaporator coil that is still under the manufacturer’s part warranty is roughly $625 – $750 in labor and incidentals alone, not including refrigerant (which is billed per pound as required to bring the system back to proper, operable charge). This can be an additional $300-$800 depending on the type of refrigerant and amount that the system can hold.
With a complete care plus extended warranty, this same repair would’ve come at a cost of a minimal deductible (currently $49 per claim, $99 as of May 1st, 2015), and would’ve likely covered your investment in the initial purchase price of the warranty.
Not only does complete care plus coverage provide you with substantial savings on repairs, it also provides added value to your home, because it’s fully transferable, should you sell your home.
Unfortunately, when it comes to mechanical devices, regardless of brand, it’s not a question of if it will fail, but rather, a matter of when. An air conditioning system in southwest Florida operates an average of 2,800 hours per year. It’s typically the equivalent of a 53+ hour work week, every week of the year, or like putting over 100,000 miles on your car in a single year! It’s hands-down, the most used, hardest working, appliance in your home.
In our opinion, this is one instance where an extended warranty is, without a doubt, a worthwhile investment.
There is an abundance of information available on the internet on the topic of coil failure and/or formicary corrosion. Please find herein a collection of information we feel offers the most comprehensive answers to the often asked question, “Why does my Coil require replacement after only a few years of service?” References are credited on […]
There is an abundance of information available on the internet on the topic of coil failure and/or formicary corrosion. Please find herein a collection of information we feel offers the most comprehensive answers to the often asked question, “Why does my Coil require replacement after only a few years of service?” References are credited on the last page of this document.
Indoor coil corrosion failures are an issue in the HVAC industry today. Although the occurrence rate of these failures is low nationwide, some geographic areas have experienced higher incidence rates. For instance, some homes experience multiple failures while those around them have none. Failures are typically characterized by leaks that form in the fin pack area of the coil after one to four years of installation and use.
This issue exists industry-wide. A competitive study has shown identical corrosion failure leaks in all coil brands investigated. The progression of the corrosion is from the exterior of the tube inward, eating away at the copper, until penetration occurs and a leak results.
There are many potential causes of coil leaks in indoor coils, ranging from manufacturing or process-related defects to copper corrosion. Additionally, there are several different corrosion mechanisms that can affect copper tubing. The following discussion focuses on pitting corrosion failures of indoor coils. There are two main forms of pitting corrosion found in indoor coils: (1) general pitting; and (2) formicary corrosion, sometimes called “ant’s nest” corrosion. General pitting corrosion is caused by aggressive anion attack on the copper tube. An anion is a negatively charged chemical species. Due to this negative charge, anions aggressively search for positively charged species called cations. Copper is an abundant source of cations. Large pits resembling bite marks characterize the footprint of general pitting. These pits can often be observed with the human eye. Chlorides are the most common source of the aggressive anions known to cause general pitting corrosion. Formicary corrosion, on the other hand, appears as multiple tiny pinhole leaks at the surface of the copper tube that are not visible to the human eye. Upon microscopic examination, the formicary corrosion pits show networks of interconnecting tunnels through the copper wall, hence the association with ants’ nests. The agents of attack involved in this corrosion mechanism are organic acids.
Common household substances that may contain chlorides include:
- Aerosol sprays
- Degreasing and Detergent cleaners
- Dishwasher detergents
- Laundry bleach
- Fabric softeners
- Paint removers
- Tub and tile cleaners
- Vinyl fabrics
- Vinyl flooring
A recent study was conducted to measure the volatile organic compound concentrations and emission rates in new manufactured and site-built houses.8 The E.O. Lawrence Berkeley National Laboratory performed this research with the support of the U.S. Department of Energy. This study shows that many materials used in the construction of new houses emit VOCs, including formaldehyde. Plywood, engineered wood products such as flooring and cabinetry, latex paint, and sheet vinyl flooring all have been identified as major sources for these compounds.
There is increasing evidence showing the home environment to be a primary contributor to coil corrosion.
- Cleaning solvents
- Foam insulation
- Paints (oil based)
- Particle boards
- Silicone caulking
- Building materials
Typical household sources of acetic acid or acetate include:1-7
- Disinfectants and deodorizers
- Tobacco and wood smoke
- Foam insulation
- Paints (latex and oil based)
- Particle boards
- Building materials
There is increasing evidence linking the primary cause of indoor coil leak failures to agents present in the household environment. Significant levels of corrosive agents known to cause these failures have been quantified in indoor condensate sampling during recent studies. The trend toward decreased home ventilation rates likely contributes to the elevated levels of indoor contaminants. In addition, increased environmental awareness to identify and fix refrigerant leaks will continue to focus attention on these indoor coil failures as an industry issue. Carrier is dedicated to continuing field and laboratory testing and research efforts to identify an effective method of preventing coil failures caused by agents in the household environment. To date, no solution has been identified that is functional, cost effective and feasible to manufacture.
- Tetley, M. Heidenreich and K. Smith, “The Basics of Formicary Corrosion,” The Air Conditioning,, Heating & Refrigeration News, March 30, 1998, pp. 5-6.
- Fairley and S. Gislason, M.D., “Handbook of Indoor Environments – Materials and Their Chemicals,” http://www.nutramed.com/environment/ handbook-materials.htm, pp. 1-8.
- Notoya, “Localized Corrosion in Copper Tubes by Volatile Organic Substance,” Journal of University of Science and Technology Beijing, Vol. 6 (1999), No. 2, p. 131.
- S. Lenox and P. A. Hough, “Minimizing Corrosion of Copper Tubing Used in Refrigeration Systems,” ASHRAE Journal, November 1995, pp. 52-56.
- Notoya, “Ant Nest Corrosion in Copper Tubing,” Corrosion Engineering, Volume 39, Number 6, p. 361.
- Elliott and R. Corbett, “Ant Nest Corrosion—Exploring the Labyrinth,” Corrosion 99, Paper No. 342, p. 2.
- T. Hodgson, A. F. Rudd, D. Beal and S. Chandra, “Volatile Organic Compound Concentrations and Emission Rates in New Manufactured and Site-Built Houses,” Indoor Air 2000, in press, ISSN 0905-6947.
- Lange, O. Wilke, D. Broedner, and O. Jann, “Measuring the Emission Behavior of Organic Acids From Wooden Products in Test Chambers,” Indoor Air 99; Volume 5.
This study was taken by Carrier on 12 major manufactures’ of air conditioning equipment in the United States and Worldwide. The information contained in this document is in part or in whole reproduce from the Carrier Corp.
Let’s face it, in Florida; air conditioning is a need, not a want. When it’s working properly, you aren’t likely to think about it … at all. But when it fails, it’s ALL you – and everyone else in the house – will be able to think about! Can it be fixed? How long will […]
Let’s face it, in Florida; air conditioning is a need, not a want. When it’s working properly, you aren’t likely to think about it … at all. But when it fails, it’s ALL you – and everyone else in the house – will be able to think about! Can it be fixed? How long will it take? How much will it cost? We’d like to share a few tips to help prevent some of those “not so cool” moments, and to help you properly care for the most important investment in your home!
- Preventative Maintenance visits offer us the opportunity to gather readings, and visually inspect you’re A/C System, while it’s operable. An Air Conditioning System in SW Florida operates an average of 2,800 hours per year, and accounts for approximately fifty-percent of your annual power costs. Much like routine physicals with your doctor, a Maintenance visit provides us with baseline readings and visual clues as to the over-all health of your System, therefore reducing the potential for unnecessary break downs.
- Cooler minds prevail! Maintenance offers you the benefit of meeting us under calm, cool, conditions. With a household of uncomfortable people, your primary concern is likely to be focused on the immediate problem at hand – You are all Hot!! Very Hot!! In a relaxed, no pressure situation, you’ll be more likely to ask questions about every day issues. Whether it’s about comfort control (Humidity? Fluctuating temperatures? Warm/cold spots?); costs to operate (efficiency); indoor air quality (allergens?); or the age of your system and whether you should be considering replacement; our Techs will be more than happy to share their hard-earned knowledge and offer sound, reasonable advice.
- Improve Efficiency! Proper Refrigerant Pressure, clean Filters & Coils and proper Amp Draws are also keys to ensuring proper, efficient operation and longevity of your System. Restricted Coils and Filters have a burdening effect on the performance of you’re a/c system.
- Improve Indoor Air Quality! Maintaining clean filters and coils plays a vital role in indoor air quality. We also offer some fabulous products designed to improve air quality above and beyond your standard pleated filter.
- Timing is everything: Our tropical summers are hard on Systems. They have to run longer, and work harder. Scheduling Maintenance visits during off-peak months (late spring and early fall) will ensure your system is in top condition, and will allow our Technicians the freedom of spending more time with you, to answer your questions and address your needs.
“I received an offer from another A/C company for Maintenance at an exceptionally low cost. Can you match this?” It’s a good question, and one we’ve been asked many times. It cost more than $29 to dispatch a technician (the tech’s time, supplies to perform the maintenance, overhead such as vehicle expenses, insurances, office personnel, […]
“I received an offer from another A/C company for Maintenance at an exceptionally low cost. Can you match this?”
It’s a good question, and one we’ve been asked many times.
It cost more than $29 to dispatch a technician (the tech’s time, supplies to perform the maintenance, overhead such as vehicle expenses, insurances, office personnel, etc.). This “Too good” offer is a way to get their foot in the door, so that they can up-sell you on profitable products you might not want, or even need. These products are typically priced higher than average, thus providing the revenue needed to cover the company’s expenses and profit, as well as a tidy little commission for the tech.
This model tends to utilize maintenance technicians (apprentices) that simply clean the system and record readings. They’re not yet qualified to interpret these readings, or experienced enough to recognize potential issues. If confronted with a problem, they’re simply not equipped to follow through with a proper diagnostic, or recommendations for repair. Unfortunately, this model doesn’t foster a true apprenticeship in our trade. It tends to promote based on sales ability, rather than technical skill, and results in many stories of good people having been taken advantage of.
We provide fully trained service technicians for every call, maintenance included, so that you’re given the opportunity to get to know our techs, and to ensure that you receive the best possible service on a personal level.
Most coil failures are actually the result of a specific coil failure known in the industry as Formicary Corrosion. This is a very specific type of corrosion that has become more and more common. It’s not to be confused with the “Chinese Drywall” syndrome the industry suffered from a few years back. Formicary Corrosion occurs […]
Most coil failures are actually the result of a specific coil failure known in the industry as Formicary Corrosion. This is a very specific type of corrosion that has become more and more common. It’s not to be confused with the “Chinese Drywall” syndrome the industry suffered from a few years back.
Formicary Corrosion occurs when a chemical compound is introduced to the blend of moisture, oxygen and metal. When the off gassing of unknown chemicals (building materials, paint, cleaning supplies, furnishings, etc.) which pass through the Indoor Coil and generate an organic acid (Formic Acid). While we’ve not found anything to indicate it’s dangerous to the occupants of the home, it can definitely have catastrophic effects on the A/C System. To date, there’s no proven corrective measure for this type of corrosion.
Manufacturers have tried using different types of copper, some converted from copper to aluminum Coils, as well as tried implementing coil coatings or even and corrosion inhibitors (sometimes called corrosion bombs), much like the anode on the back of a boat; yet the failures continue.
The problem in identifying the cause of Formicary Corrosion is that each home is as unique as its end user; from building materials, to cleaning products, to finishes and furnishing used, the possible combinations are practically limitless.
We know that manufacturers are (and have been) investing heavily in research in the goal of identifying specific components, and viable remedies; however, that’s little relief to the homeowner suffering these costly, repeat failures. As you likely know by now, the Manufacturer Parts Warranty (regardless of brand), provides only the replacement part; so replacing a warranty part, outside of the installers labor warranty, can still be quite costly. We encourage the purchase of an extended warranty.
While we agree that much has changed in the manufacturing of equipment, insofar as meeting more stringent energy efficiency codes, the largest change has been in the building envelope itself. The old norm’ was open soffits, which allowed the home to “breath”. While this wasn’t very efficient, it did allow newly constructed homes to off gas in a fraction of the time that a sealed home takes.
In meeting more stringent wind and energy codes, the sealed envelope has become the standard; and the practice it’s still relatively new to mainstream building.
Although Fresh Air Intake was added to the requirements for a sealed home, bringing in fresh air from outside, in timed increments, it doesn’t exchange air from within the home (fresh air is introduced, however, ‘stale’ air is not vented in exchange). It’s our opinion that fresh air exchange, combined with improved filtration, offers a healthier approach to regulating cleaner, healthier indoor air quality in a sealed home.
September 2015 Many components come together to create a sealed envelope in construction, but the primary (and most vulnerable) component is the spray foam, or open/closed cell, insulation used to insulate and seal your home. So, what exactly is the “building envelope”? It’s what separates the interior of the home from the exterior elements. In […]
Many components come together to create a sealed envelope in construction, but the primary (and most vulnerable) component is the spray foam, or open/closed cell, insulation used to insulate and seal your home.
So, what exactly is the “building envelope”? It’s what separates the interior of the home from the exterior elements. In a sealed envelope, every area within this barrier becomes equivalent to conditioned space (yup, even your attic), because it’s within the barrier.
The advantages of a sealed home are increased energy savings; added strength to the structure of your home; and an acting barrier to stop the intrusion of air, moisture, mold, pollutants, and dust from entering your home.
About the vulnerability: Improperly sealed gaps will result in issues (notice we didn’t say “may”). The difference in temperature and humidity that intrudes from gaps, even as small as 1″ in diameter, meeting that of the conditioned air inside the “envelope” results in condensation, which provides a breeding ground for a variety of types of mildew and mold growth. These conditions pose known health hazards, as well as costly property damage.
As an HVAC contractor, we’re typically the first to identify these types of issues, having been called in to investigate sweating ductwork or grills, mildew/mold growth, warm spots, etc.
About the picture: We were very recently called in to investigate “sweating” ductwork in the wine room of a recently complete home (our installation). The equipment has been operating since mid-January, all through the peak season of the summer, with no issues, so there was an immediate flag that we were likely looking for a breach. Sure enough, our tech found this gaping hole. If you look closely at the bottom of the frame, you can see the cut out piece of insulation is laying there right by the hole. What would’ve taken literally minutes to properly patch and reseal will now also include replacing damaged ductwork (completely saturated). This instance was actually discovered before any extensive damage or health risks evolved, but we’ve seen far worse conditions result from much smaller breaches.
The sealed envelope is not a new trend in building, so it’s a shock to us that breaches like this still occur so frequently. Nearly all breaches we come across are the direct result of a careless or uninformed act, such as the one pictured, not due to an imperfection in the original application.
We hope this article will help prevent you from incurring unnecessary problems that so often result in costly damage (to health and/or structure). Ask people you trust for referrals when you need work done on your home, be sure that you’re hiring licensed and insured professionals, and don’t be afraid to ask questions beforehand.
And if you have a sealed home, don’t let anyone in your attic without discussing this issue!